What Robert Hooke examined through a microscope. Hooke's microscope, the first microscope

Hooke can safely be called one of the fathers of physics, especially experimental, but in many other sciences he often owns some of the first fundamental works and many discoveries.

Biography [ | ]

Hooke's father initially prepared him for spiritual activity, but in view of Robert's poor health and the ability he displayed to be engaged in mechanics, he intended him to study watchmaking. Subsequently, however, the young Hooke showed an interest in scientific pursuits and as a result was sent to the Westminster School, where he successfully studied languages \u200b\u200b(Latin, Ancient Greek, Hebrew), but was especially interested in mathematics and showed a great aptitude for physics and chemistry.

His ability to study physics and chemistry was recognized and appreciated by scientists at Oxford University, where he began to study in 1653. He became assistant to the chemist Willis and later to the famous physicist Robert Boyle.

Discoveries [ | ]

Hooke's discoveries include:

and much more.

The first of these discoveries, as he himself states in his work, “ De potentia restitutiva", Published in, was done by him 18 years earlier, and in it was placed in another of his books under the guise of an anagram" ceiiinosssttuv", Meaning" Ut tensio sic vis". According to the author's explanation, the above law of proportionality applies not only to metals, but also to wood, stones, horn, bones, glass, silk, hair, etc. At present, this Hooke's law in a generalized form serves as the basis for the mathematical theory of elasticity. As for his other discoveries, in them he does not have such an exceptional primacy; so, Boyle noticed the colors of thin films in soap bubbles 9 years earlier; but Hooke, observing the colors of thin plates of gypsum, noticed the periodicity of colors depending on the thickness: he discovered the constancy of the melting temperature of ice not earlier than the members of the Florentine Academy, but the constancy of the boiling point of water was noticed by him earlier by Renaldini; the idea of \u200b\u200bthe wave-like propagation of light was expressed later by Grimaldi, albeit in a more precise, definite and pure form.

The idea of \u200b\u200bthe universal force of gravity, following Kepler, Hooke had from the mid-1660s, then, still in an insufficiently defined form, he expressed it in the treatise “ An attempt to prove the movement of the Earth”, But already in a letter to Newton on January 6, 1680, Hooke for the first time clearly formulates the law of universal gravitation and invites Newton, as a mathematically more competent researcher, to rigorously substantiate it mathematically by showing the connection with Kepler's first law for non-circular orbits (it is likely that already having an approximate solution ). From this letter, as far as we know, the documentary history of the law of universal gravitation begins. Kepler, Borelli and Bulliald are called Hooke's immediate predecessors, although their views are far enough from a clear correct formulation. Newton also owns some work on gravitation that preceded Hooke's results, but most of the most important results that Newton later recalled were in any case not communicated to them.

Invented many different mechanisms, in particular for the construction of various geometric curves (ellipses, parabolas). Proposed a prototype of heat engines.

In addition, he invented the minima thermometer, an improved barometer, a hygrometer, an anemometer, and a rain gauge; made observations in order to determine the effect of the Earth's rotation on the falling of bodies and was engaged in many physical issues, for example, on the effects of hairiness, cohesion, on weighing air, on the specific gravity of ice, invented a special hydrometer to determine the degree of freshness of river water (water-poise). In Hooke presented to the Royal Society a model of helical gears invented by him, which he later described in " Lectiones cutlerianae"(). These helical wheels are now known as White Wheels. Hooke used a cardan joint, which serves to suspend lamps and compass boxes on ships, to transfer rotations between two shafts intersecting at an arbitrary angle.

Having established the constancy of the freezing and boiling points of water, together with Huygens, he proposed these points as reference points for the thermometer scale.

Other achievements[ | ]

Villen church

Memory of Robert Hooke[ | ]

In memory of Robert in 1935, the International Astronomical Union named Robert Hooke

Price Realized: $ 96,000

HOOKE, Robert (1635-1703). Micrographia: or some Physiological Descriptions of Minute Bodies made by Magnifying Glasses. London: John Martin and James Allestry for the Royal Society, 1665. PMM 147

Leaving: $ 96,000. Christie "s. The Haskell F. Norman Library of Science and Medicine. Part II. June 15-16, 1998. New York, Park Avenue. Lot 525.

Lot description: Chancery 2o (295x193 mm). Collation: s2 (Royal Society Council "s imprimatur, title printed in red and black with engraved vignette of the Society" s coat-of-arms), A2 (author "s dedication to Charles II, his address to the Royal Society), a-g2 (preface); B-C2 D-Z4 Aa-Kk4 Ll-Mm2 (text, table, errata); 38 engraved plates, 20 of which folding, inserted where they relate to the text. The plates on three different paper stocks from the text. (A few minor stains, pl. 35 browned and mounted, tiny patch of surface damage on pl. 36, 3 plates shaved, short insignificant tears in the folds of 13 plates.) Contemporary English calf (rebacked, corners repaired), morocco fall-down-back box.FIRST EDITION, FIRST ISSUE OF THE LANDMARK WORK IN THE HISTORY OF MICROSCOPY, one of the most influential scientific books of the 17th century, containing numerous discoveries and ingenious anticipations.

The personality of Judge Sir Edmund Godfrey in England is shrouded in an aura of mystery and mystery:

Short reference:Godfrey, Edmund Berry (December 23, 1621 - October 12, 1678) - English judge and ardent supporter of Protestantism, whose mysterious death became the basis for the hoax of a papal conspiracy in England, organized by Titus Oates. Born, most likely, in Sellinge, Kent, studied at Westminster School and Christ Church in Oxford, then joined the Grace Inn (one of the forensic inns), for a time successfully engaged in the timber and coal trade. Subsequently he became a judge at Westminster, in September 1666 he received a knighthood for the execution of judicial and civil duties during the plague in London, but in 1669 he was imprisoned for several days for the arrest of the royal physician, Sir Alexander Fraser, who owed him money. ... He had a reputation as a fair judge and philanthropist. He was an ardent supporter of the Protestant religion and an opponent of Catholicism. In 1678, Titus Oates and his accomplices presented him with information about an alleged Papist conspiracy and swore to be true. They also assured Godfrey that his life was in danger, but Godfrey did not take any additional measures to ensure his own safety. On October 12, 1678, he did not return home in the evening, and on October 17, his dead body was found. Doctors, after examining the body, said that Godfrey had definitely been killed, which led to the conviction of the public that the papal conspiracy was real, and caused a wave of arrests of Catholics and massive anti-Catholic hysteria. In reality, the Papist conspiracy was the invention of Chitus Oates. Godfrey's murder has not yet been solved. Various English historians have put forward different versions of what happened, including that it could have been suicide.

Provenance: contemporary signature on verso of title and at the end of the text, apparently that of W. Brouncker as first president of the Royal Society, presumably to approve the copy; ? Sir Edmund Berry Godfrey (1621-78, justice of the peace for Westminster, knighted 1666 for his work during the plague of 1665, murdered in the panic following Titus Oates "evidence and the Popish plot) or perhaps one of his brothers, Benjamin or Michael Godfrey: This is for my highly Esteem "d freind Mr. Godfry From his very humble servant Rob: Hooke (inscribed by the author on imprimatur page); Thomas Ansell (19th-century armorial bookplate); Prof. E.N. da C. Andrade, Fellow of the Royal Society (Sotheby sale 12 July 1965, lot 261).

DEDICATION TO KING CARL II STUART

I humbly place this humble gift at the feet of Your Royal Majesty. And although it is accompanied by two shortcomings stemming from the insignificance of the author and the subject itself, I nevertheless encourage myself in both of them with the thought of the greatness of your grace and your knowledge. One taught me that you forgive even the most presumptuous, and the other that you do not neglect even the smallest in the creations of nature or craft available to your viewing. Of all the glorious deeds that have accompanied the restoration of your rule, it is far from the least that philosophy and learned sciences flourish under your royal protection. The calm prosperity of your reign has given us freedom in these pursuits, which require peace and concentration, therefore it is just that their fruits should, as a token of gratitude, be addressed to Your Majesty. Sovereign, your other subjects in your Royal Society are engaged in noble deeds: the improvement of production and agriculture, the development of trade and the improvement of navigation. In all these matters, they are assisted by the help and example of Your Majesty. Among these great tasks, I intend to present what is more consistent with the smallness of my abilities and to offer some of the most insignificant of all visible things to the mighty sovereign, who has established his empire over the best of all invisible things of this World, over the minds of people.

Your Majesty's humble and obedient subject and servant Robert Hooke

Hooke, Robert (Robert Hooke; Robert Hooke, July 18, 1635, Isle of Wight, England - March 3, 1703, in London) - English naturalist, encyclopedic scientist. Hooke can safely be called one of the fathers of physics, especially experimental, but in many other sciences he often owns some of the first fundamental works and many discoveries. Born July 18, 1635 in Freshwater on the Isle of Wight (Isle of Wight) in the family of a parish priest. As a child, he was very weak and sickly, but very early he showed a keen interest in the invention of mechanical toys and in drawing. At the age of 13, Hooke entered Westminster School and settled in the home of his school teacher, Dr. Richard Busby. At school, he studied Latin, Greek and a little Hebrew, and also got acquainted with the Principles of Euclid and some other works in mathematics. With a passion for drawing, he worked for a while and took drawing lessons from the renowned London artist Peter Lely. In 1653, Robert Hooke entered Christ Church College, Oxford University. Lacking substantial sources of livelihood, he was forced to combine his studies with the duties of a choir in the Oxford Church of Christ. In addition, he assisted, as an assistant in chemistry classes, Dr. Thomas Willis (1621-1675), the famous English physician and anatomist. In 1658, Robert Hooke graduated from college with a Master of Arts. At Oxford, while attending college, he became close to some famous scientists and, being an experienced mechanic, helped them in their research work.

Hooke's microscope (engraving from Micrography).

Around 1658 he began to work with Robert Boyle (1627-1691). In 1660, based on the results of research in which Robert Hooke took an active part, the first scientific work of R. Boyle was published, "New Experiments Physico-Mechanicall, Touching the Spring of the Air and its Effects". It describes a number of brilliant experiments in which Boyle, using a vacuum pump created by Robert Hooke (1659), demonstrated the elasticity of air, determined its specific gravity, etc. The previously known vacuum pump by Otto Guericke (the famous Magdeburg hemispheres) required strenuous efforts of two people and provided questionable results. Hooke and Boyle's vacuum pump was easily operated by one person. Boyle also demonstrated that as air is pumped out of the chamber, the character of the sound of the bell located in it changes, proving that air participates in the transmission of sound. In further experiments, he showed that air is also necessary to maintain a candle flame.

Microscope by Robert Hooke, housed in the London Science Museum.

In 1665, Hooke made important improvements in the design of the microscope and with its help carried out a number of studies, in particular, he observed thin layers (soap bubbles, oil films) in light beams, studied the structure of plants and the smallest details of living organisms, introduced the idea of \u200b\u200btheir cellular structure. In the work Micrographia (Small Figures, 1665), he described cells of elderberry, dill, carrots, gave images of very small objects, such as the eye of a fly, a mosquito and its larva, described in detail cellular structure plugs, bee wings, mold, moss. In the book we find not only information about Hooke's microscope, but also descriptions of his important new discoveries. He explained the origin of the interference coloration of soap bubbles and the phenomenon of Newtonian rings, outlined his theory of colors and explained the coloration of thin layers by the reflection of light from their upper and lower boundaries. Hooke was an opponent of Newton's corpuscular theory of light and formulated a hypothesis about the transverse nature of light waves, suggesting that "light is a very short oscillatory motion, occurring in transverse directions to the lines of propagation of light."

Hooke's discoveries include:

The discovery of proportionality between elastic stretches, compressions and bends, and the stresses that produce them (Hooke's law),

The correct formulation of the law of universal gravitation (Hooke's priority was disputed by Newton, but apparently not in terms of the formulation; in addition, Newton argued about an independent and earlier discovery of this formula, which, however, did not tell anyone before Hooke's discovery),

The discovery of the colors of thin films (that is, ultimately, the phenomenon of light interference),

The idea of \u200b\u200bwave-like propagation of light (more or less simultaneously with Huygens), experimental substantiation of it by the interference of light discovered by Hooke, wave theory of light,

Hypothesis about the transverse nature of light waves,

Discoveries in acoustics, for example, the demonstration that pitch is determined by the frequency of vibrations,

The theoretical position on the essence of heat as the movement of body particles,

Discovery of the constancy of the temperature of melting ice and boiling water,

Boyle's Law (what is the contribution of Hooke, Boyle and his student Richard Townley is not completely clear),

Living cell (with the help of a microscope improved by him; Hook owns the very term "cell" - English cell).

So, as we already wrote, in 1665 Robert Hooke's major work - "Micrographia", was published, dedicated to the results of observations by a 28-year-old author using a variety of lenses. Published in September 1665, the book immediately became a bestseller. Hooke remarkably describes the flea eye and the plant cell (he coined the term because plant cells, enclosed by walls, reminded him of a monk's cells). This was not only a presentation of the results of a fundamentally new application of the microscope as a research tool. The book is much broader and deeper. It describes 57 "microscopic" and 3 "telescopic" experiments. Hooke studies plants, insects and animals and makes the most important discoveries concerning not only individual organs, but also the cellular structure of tissues. Looking at the fossils, Hooke, in fact, acted as the founder of paleontology. Hooke supplied the book with excellent engravings made by him and representing independent and scientific and even artistic interest. The author of "Mikrografiya" puts forward original ideas concerning light, gravitation and the structure of matter. Known for its outstanding copper engravings of the microcosm, in particular the folding sheets of insects, the book confirms the extraordinary capabilities of the new microscope. The unfolded insect prints are larger than the folio itself, which is large enough. In particular, the full size of the print of a flea is four times the size of a book. Although the book is best known for demonstrating the capabilities of the microscope, it also contains descriptions of distant planetary bodies, wave theory of light, the organic origin of fossils, and other philosophical and scientific interests of the author. Published with the support of the Royal Society, the book's popularity has helped shape the image and mission of society as a scientifically progressive organization in London. In the same book, he discussed the possibility of producing artificial fibers using processes similar to the spinning of a silkworm, and was the first to use the word "cell" (cell) to name the microscopic honeycomb pores in the cork. His work with the microscope was carried out at the highest level for his time, and it is to Robert Hooke that we owe the word "cell". Research into microscopic fossils made him one of the earliest proponents of evolutionary theory.

Hooke is constantly inventing. So, he comes up with a calculating machine that allows you to perform any arithmetic operations, improves the device for studying the Earth's magnetic field. He often enters into discussions with other scientists. So, in 1674, he argues with Jan Hevelius, defending the idea of \u200b\u200busing telescopes in goniometric instruments. Sometimes, we have to admit, the discussions are too harsh, especially when it comes to priority issues. From the works of the second half of the 1670s. especially one can single out research on the theory of elasticity, the main result of which was the famous Hooke's law. If, for example, the elongation of a wire under the influence of a certain force is considered, then this law is formulated as follows: the relative elongation (i.e., the increase in length referred to the initial length), is proportional to the magnitude of this force, inversely proportional to the cross-section of the wire and depends on which material it is made. Hooke even realized that such a law is valid only in the case of small deformations.

The invention of the microscope began when Galileo once built a very long telescope. It took place during the day. When he finished his work, he aimed the pipe at the window to check the cleanliness of the lenses in the light. Clinging to the eyepiece, Galileo was dumbfounded: the entire field of view was occupied by some kind of gray sparkling mass. The pipe swayed slightly, and the scientist saw a huge head with bulging black eyes on the sides. The monster had a black body with a green tint, six knee-legged legs ... Why, it's ... a fly! Taking the pipe away from his eyes, Galileo was convinced that there was indeed a fly on the windowsill.

This is how the microscope was born - a device consisting of two lenses for enlarging the image of small objects. Its name - "microscope" - he received from a member of the "Academy dei lynchei" ("Academy of lynx-eyed")

I. Faber in 1625 It was a scientific society, which, among other things, approved and supported the use of optical devices in science.

And Galileo himself in 1624 inserted shorter focus (more convex) lenses into the microscope, due to which the tube became shorter.

Robert Hooke and his achievements

The next page in the history of microscope creation is associated with the name of Robert Hooke. He was a very gifted person and a talented scientist. Hooke's most significant achievements are as follows:

• invention of a coil spring for adjusting the clock; creation of helical gears;
• determination of the speed of rotation of Mars and Jupiter around their axis; invention of the optical telegraph;
• creation of a device for determining the freshness of water; creation of a thermometer for measuring low temperatures;
• establishing constancy of ice melting and water boiling temperatures; discovery of the law of deformation of elastic bodies; the assumption of the wave nature of light and the nature of gravity.

After graduating from Oxford University in 1657, Hooke became an assistant to Robert Boyle. It was an excellent school for one of the greatest scientists of the time. In 1663, Hooke was already working as a secretary and demonstrator of the experiments of the English Royal Society (Academy of Sciences). When it became known about the microscope, Guk was instructed to conduct observations on this device. The Drebbel microscope at his disposal was a half-meter gilded tube, located strictly vertically. I had to work in an uncomfortable position - bending over in an arc.

Improving the microscope by Hooke

First of all, Hooke made a pipe - a tube - inclined. In order not to depend on sunny days, which are few in England, he installed an oil lamp of an original design in front of the device. However, the sun was still shining much brighter. Therefore, the thought came to intensify and concentrate the rays of light from the lamp. This is how Hooke's next invention appeared - a large glass ball filled with water, and behind it a special lens. Such an optical system increased the brightness of the illumination hundreds of times.

The resourceful Hooke easily coped with any difficulties that appeared on his way. For example, when he needed to make a very small lens of perfectly round shape, he dipped the tip of the needle into the molten glass and then quickly took it out - a droplet sparkled at the tip of the needle. Hooke polished it down a bit and the lens was ready. And when it became necessary to improve the quality of the image in the microscope, Hooke inserted a third, collective, between two traditional lenses - the objective and the eyepiece, and the image became clearer, while the field of view increased.

When the microscope was ready, Hooke began to observe. He described their results in his book "Micrography", published in 1665. For 300 years, it was reprinted dozens of times. In addition to descriptions, it contained wonderful illustrations - engravings by Hooke himself.

Discovery and discovery, cell structure

Of particular interest in it is observation No. 17 - "On the schematism, or the structure of the cork and on the cells and pores of some other empty bodies." Hooke describes a cut of an ordinary cork like this: "It is all perforated and porous, like a honeycomb, but its pores are irregular in shape, and in this respect it resembles a honeycomb ... Further, these pores, or cells, are shallow, but consist of many cells separated by partitions." ...

In this observation, the word "cell" is striking. So Hooke called what is now called cells, for example, plant cells. In those days, people did not have the slightest idea about it. Hooke was the first to observe them and gave a name that remained with them forever. This was a discovery of enormous importance.

Observations by Anthony van Leeuwenhoek

Soon after Hooke, the Dutchman Anthony van Leeuwenhoek began his observations. He was an interesting person - he traded in fabrics and umbrellas, but did not receive any scientific education. But he had an inquisitive mind, observation, perseverance and conscientiousness. Lenses, which he polished himself, magnified the object 200-300 times, that is, 60 times better than the devices used then. All his observations he set out in letters that he carefully sent to the Royal Society of London. In one of his letters, he reported on the discovery of the smallest living creatures - the animalul, as Levenguk called them.

It turned out that animalculi are present everywhere - in the earth, in plants, in the body of animals. This event revolutionized science - microorganisms were discovered.

In 1698, Anthony van Leeuwenhoek met with the Russian emperor Peter I and showed him his microscope and animalculus. The emperor was so interested in everything that he saw and what the Dutch scientist explained to him that he bought microscopes from Dutch masters for Russia. They can be seen in the Kunstkamera in St. Petersburg.

Another important discovery belongs to Levenguk. By heating the water to a boil, he noticed that almost all the animals die. This means that in this way you can get rid of pathogens in the water that people drink.

Pinhole camera

Concluding the conversation about optical instruments, it is necessary to mention the camera obscura, invented in 1420 by the Italian engineer G. Fontana. A pinhole camera is the simplest optical device that allows you to get images of objects on the screen. It is a dark box with a small hole in one of the walls, in front of which the object in question is placed. The rays of light emanating from it pass through the hole and create an inverted image of the object on the opposite wall of the box (screen).

In 1558 the Italian G. Porta adapted a camera obscura for the execution of drawings. He also came up with the idea of \u200b\u200busing a camera obscura for projecting drawings placed at the opening of the camera and strongly illuminated by candles or the sun.

The message about, which is set forth in this article, will tell about the English naturalist, physicist and researcher.

Robert Hooke's contributions to biology. What did Robert Hooke discover?

Robert Hooke's contributions to biology is that he was the first to use the microscope for the study of animal and plant tissues. Studying the cut of the elderberry core, the scientist saw that it consists of a large number of small formations. Hooke called them cells.

Brief information about Robert Hooke

The parents wanted their son Robert to devote his life to spiritual work. Due to poor health and passion for mechanics, Hooke was sent to study watchmaking. Later, the young man showed an interest in science and began to study at Westminster School. Here the future scientist studied mathematics, mechanics, physics and languages. Thanks to his sharp mind, Hooke entered Oxford University in 1653.

Robert Hooke discoveries in biology

At the university, he began to study the physical properties of ordinary cork. He was greatly interested in the question of why it has a high buoyancy. In order to find out, Hooke made many observations, making cuts on the cork and studying them under a microscope. During his research, the scientist revealed that it consists of a large number of small cells, similar to monastic cells. In 1665, Robert Hooke first described how these partitioned cells are arranged. He described the results of observations in the work "Micrography, or some physiological descriptions of the smallest bodies, made with magnifying glasses." In it, the scientist first used the term "cell". Then the naturalist studied the cut of the elderberry core and the cork, examining under a microscope all the same formations, similar to cells from a honeycomb. Although, in fact, he considered not the cells themselves, but their shells. This is how Robert Hooke opened the cage.

In addition to studying the cell, the scientist in his book described the origin of minerals, distant planetary bodies and questions of the theory of light. His work "Micrographia" aroused genuine interest in scientific circles.

What did Robert Hooke discover?

In addition to biology, scientist Robert Hooke was fond of studying fossils. Therefore, he is also considered the founder of paleontology. In addition, he illustrated his book with his own hand and made engravings for it. The scientist invented a computer for arithmetic complex operations and modernized the device that studied the magnetic field of the planet.

We hope that from this article you have learned what the discovery was made by Robert Hooke.

July 18, 1635 On this day, a famous English naturalist was born Robert Hooke (Hooke, Robert, 1635-1703), who also went down in the history of the ISS, thanks to his experiments on artificial ventilation with the help of furs on animals (1667). These experiments took place in the framework of research on the circulatory and respiratory systems, conducted by the famous "Oxford Group", which founded the Royal Society of London.
However, it should be noted that as early as 1530 Philip Aureol Theophrastus Bombast von Hohenheim (Philippus Aureolus Theophrastus Bombastus von Hohenheim, 1493-1541), better known as Paracelsus, used fireplace bellows and a special oral air duct for ventilation.

HOOK, ROBERT (Hooke, Robert, 1635-1703), the famous English natural scientist. Born July 18, 1635 in Freshwater on the Isle of Wight (Isle of Wight) in the family of a parish priest. As a child, he was very weak and sickly, but very early he showed a keen interest in the invention of mechanical toys and in drawing. At the age of 13, Hooke entered Westminster School and settled in the home of his school teacher, Dr. Richard Busby. At school, he studied Latin, Greek and a little Hebrew, and also got acquainted with the Principles of Euclid and some other works in mathematics. With a passion for drawing, he worked for a while and took drawing lessons from the renowned London artist Peter Lely.
In 1653, Robert Hooke entered Christ Church College, Oxford University. Lacking substantial sources of livelihood, he was forced to combine his studies with the duties of a choir in the Oxford Church of Christ. In addition, he helped as an assistant in chemistry classes to Dr. Thomas Willis (Thomas Willis, 1621-1675), the famous English physician and anatomist. In 1658, Robert Hooke graduated from college with a Master of Arts degree.
At Oxford, while attending college, he became close to some famous scientists and, being an experienced mechanic, helped them in their research work. Around 1658 he began to work together with Robert Boyle (Robert Boyle, 1627-1691). In 1660, based on the results of research in which Robert Hooke took an active part, the first scientific work of R.Boyle was published "New Experiments Physico-Mechanicall, Touching the Spring of the Air and its Effects" ... It describes a number of brilliant experiments in which Boyle, using a vacuum pump created by Robert Hooke (1659), demonstrated the elasticity of air, determined its specific gravity, etc. The previously known vacuum pump by Otto Guericke (the famous Magdeburg hemispheres) required the strenuous efforts of two people and provided questionable results. Hooke and Boyle's vacuum pump was easily operated by one person. Boyle also demonstrated that as air is pumped out of the chamber, the character of the sound of the bell located in it changes, proving that air participates in the transmission of sound. In further experiments, he showed that air is also necessary to maintain a candle flame.

In 1662, the second edition of this book was published, in which Boyle was the first to formulate the law of change in the volume of gases (in particular, air) with a change in pressure, which later received the name of Boyle-Mariotte's law. Independently of Boyle, this law was formulated in 1676 by the French physicist Edm Marriott. In fairness, it should be noted that a huge contribution to the success of Robert Boyle was made by his assistant Robert Hooke, who made the pump himself, and took an active part in a three-year cycle of experiments.
Around 1660, Robert Hooke, together with Christian Huygens (Christian Huygens, 1629-1695) set the reference points for the thermometer scale - the temperature of melting ice and boiling water.
In 1662, on the recommendation of Robert Boyle, Hooke became the curator of the organization of experiments in the newly formed Royal Scientific Society of London, and his knowledge of mechanics and inventive ability were put to good use here. He always strove to develop some kind of device in order to demonstrate his own ideas, or in order to illustrate or clarify any issue that arose in the discussions of the members of the Society. And from 1677 to 1683, Robert Hooke served as secretary of this society. On duty, he was obliged to reproduce at meetings all the experiments, reports of which were received by the Society. Only a brilliant experimenter and engineer-inventor could cope with this task. Fortunately, Robert Hooke was just that.
Collaborating with the Oxford Scientific Group, which included Robert Boyle (Robert Boyle, 1627-1691); Thomas Willis (Thomas Willis, 1621-1675); William Petty (William Petty, 1623-1687); architect Christopher Wren (C. Wren, 1632-1723); John Locke (John Locke, 1632-1704); John Mayow (John Mayow, 1643-1679); Richard Lover (R.Lower, 1631-1691), and others, Robert Hooke took an active part in the group's medical experiments aimed at studying respiration and blood circulation.
One of the members of this group, Richard Lover, discovered that the dark venous blood flowing into the air-filled lungs becomes a bright red color, on the basis of which he came to the conclusion that the blood absorbs "something from the air" in the lungs. And he showed that this process of changing the color of blood does not take place in the heart, but in the lungs by means of air, or some component of the air, which he sometimes calls the "nitrous spirit" that enters the blood during breathing, and the fact that this entry of air into the blood is very important for living organisms.
Another active member of the "Oxford Group" John Mayow (John Mayow, 1643-1679), continuing Loveer's experiments, drew attention to the fact that during breathing, not all air enters the blood, but only a certain component of it, necessary for life and combustion, which causes a change in the blood circulating in the lungs ... Consequently, Mayou, 100 years before Lavoisier, discovered a chemical link between breathing and combustion. Mayow is also known for being the first to discover the expansion of the right ventricle in mitral stenosis. Thus, he initiated the study of the consequences of impaired heart function.
At first glance, the research activities of the members of the "Oxford Scientific Circle" may seem somewhat chaotic, and their experiments from the height of modern knowledge look primitive and even naive. However, upon careful analysis of the results of the research carried out by the "Oxford Group", one can, for example, see that these enthusiasts of science created an advanced teaching about breathing for that time. Notice how interesting the logical chain is in their experiments. The main scientific and ideological inspirer of the Oxford Group, Robert Boyle, proves that air is necessary for combustion and maintenance of life; his assistant, Robert Hooke, conducts artificial respiration experiments on dogs and proves that it is not the movement of the lungs by itself, but the air that is the most important condition for breathing; Richard Lover highlights the problem of air-blood interaction by showing that blood turns bright red when exposed to air and deep red when artificial respiration is interrupted. The final point is put by John Mayow, proving that not air itself, but only a certain component of it, is necessary for combustion and life. True, John Mayow, assumed that this necessary component is a nitrogen-containing substance. In fact, he actually discovered oxygen, which was named so only as a result of his second discovery By Joseph Priestley (Joseph Priestley, 1733-1804).
In 1663, Robert Hooke (like the Dutch scientist Anthony van Leeuwenhoek) became interested in microscopy and first discovered the cellular structure of plant tissues.

Anthony van Leeuwenhoek (Antony van Leeuwenhoek, 1632-1723)

In 1665, Hooke made important improvements in the design of the microscope and, with its help, carried out a number of studies, in particular, he observed thin layers (soap bubbles, oil films) in light beams, studied the structure of plants and the smallest details of living organisms, introduced the idea of \u200b\u200btheir cellular structure. In work Micrographia (Small Drawings, 1665) he described cells of elderberry, dill, carrots, gave images of very small objects, such as the eye of a fly, mosquito and its larva, described in detail the cellular structure of the cork, bee's wing, mold, moss. In the book we find not only information about Hooke's microscope, but also descriptions of his important new discoveries. He explained the origin of the interference coloration of soap bubbles and the phenomenon of Newtonian rings, outlined his theory of colors and explained the coloration of thin layers by the reflection of light from their upper and lower boundaries. Hooke was an opponent of Newton's corpuscular theory of light and hypothesized about the transverse nature of light waves, suggesting that "Light is a very short oscillatory motion in transverse directions to the lines of propagation of light" .

In the same book, he discussed the possibility of producing artificial fibers using processes similar to the spinning of a silkworm, and was the first to use the word "cell" (cell) to name the microscopic honeycomb pores in the cork. His work with a microscope was carried out at the highest level for his time, and it is to Robert Hooke that we owe the word "cell". Research into microscopic fossils made him one of the earliest proponents of evolutionary theory.

However, he could not yet observe the inner life of the cell. Robert Hooke did not have a chance to prove by observation and hypothesis William Harvey (William Harvey, 1578-1657) about the complete closure of the two circles of blood circulation. This was later done by a foreign member of the Royal Society of London - an Italian physician from Bologna Marcello Malpighi (Marcello Malpighi, 1628-1694), who opened the capillaries - the smallest vessels that connect the arteries and veins. Another doctor, Jan Swammerdam (Jan Swamerdam, 1637 - 1680) from Amsterdam, found erythrocytes in the blood. But, despite these great discoveries, science of the 17th century has not yet been able to establish the overall physical essence of blood circulation and respiration.

In 1665, Hooke became professor of geometry at Cresham College London, but he continued to demonstrate his experiments, invent and describe new instruments at the Royal Society.

After the Great Fire of London in September 1666, Hooke presented a model illustrating his project for the reconstruction of the damaged city, after which the members of the city magistrate commissioned Hooke to carry out this restoration work. He was very active in rebuilding London and personally designed several buildings. Many historians associate the restoration of London after the fire solely with the name of the famous architect Christopher Ren (C. Wren, 1632-1723), although few people know that Ren's success was largely due to the extraordinary participation in the work of his friend Robert Hooke. Hooke was one of three magistrate-appointed peer inspectors, including Ren, who oversaw the reconstruction of London. Some of Robert Hooke's projects are still incorrectly attributed to Christopher Rahn.
For example, the dome of the famous St. Paul's Cathedral in London was built on the basis of mathematical calculations by Robert Hooke. In the middle cross of the cathedral, at a height of 30 m, the foundation of a dome with a diameter of 34 m, which rises to 111 m, was laid. Robert Hooke advised Ren to use a unique solution during the joint work on the dome project. Immediately above the cross, they erected the first dome in brick with a round 6-meter hole at the top (oculus), fully proportional to the proportions of the interior. Above the first dome, the architects erected a brick cone, which serves as a support for a massive stone lantern, weighing up to 700 tons, and above the cone, a second dome covered with lead sheets on a wooden frame, proportionally correlated with the external volumes of the building. An iron chain is laid at the base of the cone, which takes over the lateral thrust. A slightly pointed dome, resting on a massive circular colonnade, dominates the appearance of the cathedral.

The following story illustrates the skill of Christopher Ren and Robert Hooke. When the cathedral was almost built, the city authorities drew attention to the fact that in the central space of the temple there are no columns that would support the huge ceiling. Christopher Ren convinced that the columns were not needed and the ceiling would not collapse, and cited his calculations and the calculations of Robert Hooke as proof. However, they did not believe him and ordered to support the ceiling of the cathedral with columns. Ren fulfilled this requirement, but ... the columns he erected do not reach the ceiling, there is space between the capitals and the ceiling itself. These columns, not supporting the ceiling, still stand today, being a symbol of the highest skill of architects and the usual mistrust of the authorities in the achievements of science.
The space between the two domes of the cathedral has formed the famous "whispering gallery", in which a word spoken in a whisper against one wall becomes clearly audible against the opposite wall of the dome. Although this sound phenomenon is, in principle, quite typical for dome structures, it should be noted that by this time Robert Hooke was well versed in the physics of sound. He conducted various experiments with sound and its conduction in various environments, and by this time he had also invented the auditory tube. The whispering wall effect was also used by Robert Hooke in the design of the Montague House building.

The range of scientific interests of Robert Hooke was very wide: heat, elasticity, optics, celestial mechanics ...
At a meeting of the Royal Society on May 3, 1666, Robert Hooke stated:
“I intend to set forth a system of the world that is very different from all so far proposed; it is based on the following three principles:
I. All celestial bodies not only possess the gravitation of their parts to their own common center, but are also attracted mutually to one another within their spheres of action.
II. All bodies, making a simple motion, will continue to move in a straight line, unless they constantly deviate from it by some external force that induces them to describe a circle, ellipse, or some other curve.
II. This attraction is greater the closer the bodies are. As for the relationship in which these forces decrease with increasing distance, I myself (as he reports) did not define it, although I did some experiments for this purpose. I leave it to others who have enough time and knowledge for this task. "
As we can see, Robert Hooke had a fairly clear idea of \u200b\u200buniversal gravitation, although he lacked the mathematical knowledge to prove Kepler's laws. He suggested that the force of gravity could be measured using the movement of a pendulum and tried to show that the Earth and the Moon move in an ellipse around the Sun. In 1678, to describe planetary motions and prove that all planets must move in elliptical orbits, he established the inverse quadratic law, according to which attraction is inversely proportional to the square of the distance. In essence, this law was Newton's law of universal gravitation (Isaac Newton, 1642-1727), later proposed by Newton in a more perfect and modified form. Hooke complained that he was not believed when he discovered this law and got involved in an argument with Newton. I must say that the relationship between these two scientists has always been very bad, which is quite vividly described in books on the history of science.
Not being a professional astronomer, Robert Hooke discovered in 1664 a double star (the second in the history of astronomy). He was the first to build a completely new Gregorian reflecting telescope, with which most of the new stars were discovered. Hooke also discovered the fifth star in Trapezium, a star in the constellation Orion, and was the first to suggest that Jupiter rotates on its axis. His detailed sketches of Mars were used even in the 19th century to determine the speed of rotation of this planet.
Robert Hooke is also referred to as the father of British meteorology, and Hooke's barometer can now be seen in the Science Museum in London.

Robert Hooke was the first scientist to investigate the elasticity of physical bodies. In 1678 his work came out of print "De potentia restitutiva or of spring" (About restorative ability or elasticity). It contains the results of Hooke's experiments with elastic bodies. This was the first published work in which the elastic properties of materials were considered. The linear relationship between force and deformation revealed by him, now known as Hooke's law, served as the foundation on which the mechanics of elastic bodies subsequently received its further development. He applied this knowledge to the design of clocks and built the first spring-loaded clocks, more accurate than Huygens' pendulum clocks.
In 1672, he discovered the phenomenon of diffraction of light (light wraps around corners so that shadows are always blurred). More important in this phenomenon is that in the shadow behind the subject, light appears in an alternation of light and dark stripes. To explain this, Hooke proposed a wave theory of light. On this basis, he had his first conflict with Isaac Newton, which gradually turned into a long-term enmity. Newton began to be interested in optics as a student, his research in this area was associated with the desire to eliminate the shortcomings of optical devices. In his first job "New theory of light and colors" reported by him to the Royal Society of London in 1672, Newton expressed his views on "Corporeality of light" (i.e. corpuscular hypothesis of light).
This work of Newton caused a stormy controversy: at that time, wave representations dominated. Robert Hooke was a particularly fierce opponent of corpuscular views on the nature of light. Answering Hooke, Newton formulated a hypothesis that combined corpuscular and wave concepts of light. He later developed this hypothesis in the essay "Theory of light and colors" , in which he also described his experiments with "Newton's rings" and established the periodicity of light waves.
However, when reading this essay at a meeting of the Royal Scientific Society of London, Hooke made a claim for priority, and an irritated Newton decided not to publish optical works. Newton's long-term optical studies were published by him only in 1704 - a year after Hooke's death - in a fundamental work "Optics" .
Incidentally, Robert Hooke was the first scientist to establish in general terms that all matter expands when heated, and air consists of particles separated from each other by relatively large distances. His model with springs between atoms was later adopted by the same Isaac Newton.

What was the true place of Robert Hooke in science? For example, his student patron, the aristocrat Robert Boyle, was and is a better known scientific figure than Robert Hooke, the son of a poor priest and permanent secretary of the Royal Society. The point is that even a new science that devoted itself to experiment, in practice, always gave preference to theorists. The fact that Hooke is known only in a narrow circle of specialists is partly due to the greater inclination of scientists to theory than to experiment, as well as the fact that, unlike the aristocrat Boyle, Hooke was a poor self-taught. The difference in the theory / experiment ratio is modeled here by social status. Even Robert Hooke, an experimenter who also theorized, is now almost forgotten, while Robert Boyle, a theoretician who also experimented, is still mentioned in high school textbooks. Interestingly, Boyle's important chemical experiments are now much less remembered, while Robert Hooke has a reputation for being a pure experimenter, but his theoretical insights are largely ignored. Hooke was the curator of experiments at the Royal Society, and had the character of a grumpy old man who easily got into conflicts, in part because of his low position as an experimenter. Yet Robert Hooke definitely deserves a place in the pantheon of scientific glory, as evidenced by his many scientific achievements, as reflected in this issue of our Virtual Calendar.
Hooke died in London, March 3, 1703, and was buried in St. Helena's Church.