This great encyclopedia of the natural sciences was the first scientific work to be done on a printing press. During the Middle Ages it had remained an authoritative source of scientific knowledge, and in this magnificent edition its influence continued. The present copy is splendidly illuminated.

Euclid's lucid explanation of geometrical principles has survived all but unchanged more than 2,000 of the most changeful years in man's history. It is the only ancient textbook that has remained in use to our own day. Ratdolt's 1482 edition was the first printed in any language.

Ptolemy's work in geography was as influential on that science as his Almagest was on the development of astronomy. His was the most successful of early attempts to put the study of geography on a scientific basis. This famous edition contains thirty-two hand-colored woodcut maps.

This is the second edition but the first to contain the woodcuts of the activities of physicians and surgeons for which the book is famous. They are the first realistic medical illustrations. The famous dissection woodcut, printed in four colors, is one of the few known examples of multicolor printing in the incunabula period.

The work of no other Greek physician had greater or more enduring influence than that of Hippocrates. His great ethical code became an inseparable part of practical medicine from his generation to our own. This volume contains the Aphorisms, with comments by Galen. Only two other copies are recorded in America.

Ptolemy's great work on astronomy was authoritative for 1,300 years. So firmly did his theories weld the earth at the center of the universe that not until Copernicus could it be jarred loose. This first adequately translated edition was begun by Peurbach and finished by his famous pupil Regiomontanus.

No copy of the first edition of this popular medical work, one of the earliest written in the vernacular, is known to exist. Of the second edition, shown here, only one other copy is recorded. Elyot was not a member of the medical profession, a fact which resulted in considerable criticism in professional circles. This copy is bound with Thomas Paynel's translation of Regimen Sanitatis Salerni (London, 1535), also a scarce work.

Copernicus' great book shifting the earth from the center of the universe to an orbit around the sun held implications that fundamentally affected the lives of all later generations. This is one of the very few copies containing both title pages, with and without the errata printed on the verso.

Vesalius made greater strides away from traditional anatomical procedure than any of his contemporaries. Still, because of his deep education in Galenic theory, he was never able to break completely from traditional ideas. His book emerged inevitably that mixture of originality and tradition characteristic of so many of the great milestone books in the different fields of intellectual endeavor. In its massive format and striking illustrations, De Fabrica is one of the most beautiful books ever produced.

The brilliant achievements of Archimedes in mathematics, mechanics, astronomy, and physics are here printed for the first time in the language in which he wrote them.

This volume contains the first organized works on physical geology and mineralogy as well as sections devoted to subterranean waters and gases, topographical mineralogy, and the history of metals. Agricola was a pioneer in the study of the formation of ore deposits.

Here for the first time were presented accurate and detailed descriptions of various mining operations. The product of twenty-five years' careful research, De Re Metallica was the first classic of modern mining technology, remaining the unchallenged authority in its field for over two hundred years. The first translation into English was by Mr. and Mrs. Herbert Hoover, 1912.

Printed by Juan Pablos, the New World's first printer, this is the first work of science published in the Western Hemisphere. It is based primarily on Aristotelian natural science. Wagner, while compiling his Nueva Bibliografia, was able to locate only six perfect copies.

Although Cesalpini's most significant work was done in botany, he came close in his physiological investigations to a formulation of the circulation of the blood. His theories in the field, however, were ignored, and fundamental work on the greater circulation was not done again until Harvey.

This beautiful little volume, perhaps the most important work of the famous French doctor, contains his teachings on bandages, fractures, and dislocations.

Bartisch's book is the most famous of all early works on eye surgery. This copy contains all the superimposed flaps.

Avicenna's is the most famous medical textbook ever written. Based on the great works of Galen, it served as the guide to medical study in European universities from the twelfth to the seventeenth century. This superb copy is from the library of the Prince of Liechtenstein.

This is one of the pioneer works on plastic surgery. Tagliacozzi's work was rejected both by his fellow doctors and by the Church, which regarded such changes of God-given features as unnatural.

One of the most important scientific works ever published, Gilbert's book codified man's knowledge of magnetism and introduced the momentous science of electricity. Gilbert was among the first to demonstrate the new experimental methods which were to free science at last from the halters of unquestioned authority.

This, Kepler's greatest book, contains his first two laws of planetary motion. Together, his three laws provided important keys for Isaac Newton in the development of his theory of universal gravitation.

Napier was the inventor of logarithms. The Canonis Descripto is one of the key books in his development of this immensely useful branch of mathematics.

Here Kepler sets down for the first time his third great law of planetary motion: the square of the period of a planet's revolution is proportional to the cube of its mean distance from the sun. This fine copy belonged to Hermann, Landgrave of Hesse, whose father was Kepler's patron. It also bears the bookplate of the famous Nordkirchen library.

This copy of Bacon's famous exposition of a new and modern scientific method is one of seven recorded large-paper presentation copies especially bound in vellum for Sir Francis, with his arms in the form of a wild boar stamped in gold on the covers. The Pforzheimer catalogue states: "to possess such a book is surely to attain the height of bibliophilic pleasure."

By careful observation and experiment Harvey established the circular course of the blood as it is driven by the pumping heart through the body's arteries and veins. That momentous discovery was published for the first time in this small book, which has been called the most valuable book in the history of medicine.

In the form of conversations between supporters and a detractor of the Copernican system, Galileo presented a mortal attack on Aristotelianism and answered the two most fundamental criticisms brought against Copernicus: absence of stellar parallax and vertical fall of bodies. The book also contains Galileo's theory of tides and the results of his telescopic observations of the heavens.

Descartes' method of achieving true knowledge by intuition and deduction had tremendous influence on the development of seventeenth- and eighteenth-century science. His book contains essays on optics, meteors, and geometry. In the latter, Descartes laid the foundations of analytic geometry.

Galileo for the first time applied the concept of inertia to moving bodies. By experiments with inclined planes, pendulums, and projectiles, he made fundamental advances in the fields of dynamics and mechanics. He initiated the study of the strength of materials.

This copy of Ray's scarce first book, the first catalogue of local plants to be issued in England, has both title pages. Only a few such copies are known. For a small book it contained a great deal of plant information of importance to the advance of English botany.

Boyle attempted to elevate chemistry to an independent experimental science. In this book he developed his "corpuscular" theory, which had important implications for the development of modern chemistry.

Boyle's famous law concerning the inverse variation between the volume and pressure of a gas was first stated in this second edition of New Experiments. Important theories on the properties of air were also established.

Hooke's work was the first to deal exclusively with microscopic observations. Throughout, immensely fertile ideas in a variety of fields are presented, including the first description of the cellular structure of plants.

This is the rare first issue of this famous book on respiration and the circulation of the blood, the first important experimental advance in that field after Harvey. This earliest issue contains leaf A6, an attack on the Irish physician Mearn, uncanceled. It is one of the rarest of medical classics.

Von Guericke was one of the pioneers of experimental science. He invented the air pump, created the first electrostatic machine, and did important work in the study of atmospheric pressure.

Huygens, who invented the pendulum clock, developed in this book the mathematical theory of pendulum motion. He also printed for the first time the laws of centrifugal force, though without proofs. These were the greatest accomplishments in the science of mechanics between the time of Galileo and that of Newton.

Borelli did much to extend the knowledge of the circulatory system initiated by Harvey. In the two volumes of De Motu Animalium he attempted to apply the laws of mechanics and physics to the movement of animals. It was Borelli who first declared the heart beat to be the result of muscular contraction.

Grew was the discoverer of the sexuality of plants. He recognized for the first time that a plant's sexual life exists in its flower. His theories were published in their most complete form in this work.

Newton here advanced his three famous laws of motion and developed his theory of universal gravitation, unquestionably one of the greatest achievements in the history of scientific development. The two variant states of the title page are exhibited.

Bernoulli's remarkable development of the calculus of probability and the theory of combinations qualify him as one of the giants of mathematics. In the final section of this important book he applied his calculus of probability to civil, moral, and economic conditions, marking the entry of mathematics into new fields.

This volume of Hales' famous Statical Essays contains his important experiments on plant physiology in which he demonstrated the dependence of plants on air, described the rate of plant growth, the movement of sap, and the nourishment provided by the air.

Both as an item of importance in the history of physiology and as a very early and most successful experiment in color printing, this treatise on the location and cause of the colored skin of Negroes is a remarkable volume. The plate is one of the rare surviving examples of the work of Jan Ladmiral, a pioneer in the process of color printing.

Franklin's great clarity of style contributed a good deal to the importance of his work in electrical science. His book was translated widely in the eighteenth century and exerted an especially strong influence in France.

The basic principles of photometry were presented for the first time in this classic work in optics. Little was done subsequently in the measurement of light that Lambert had not already touched upon.

Priestley collected his important experiments and discoveries on air into several volumes of which this was the first. To Priestley belongs the credit of having first experimentally produced oxygen, which he called "dephlogisticated air."

Written by an army doctor who intended it be used in army hospitals, this was the first pharmacopoeia published in America. The book is extremely hard to come by, only seven other copies being located, five of them in Philadelphia libraries.

Hutton read his theory to the Edinburgh Royal Society in 1785. Controversial at the time, his brilliant explanation of earth formation and continued change, based on years of careful observation, has since become a classic example of scientific investigation. The off-print from the Transactions displayed here was later expanded into a two-volume work which contained much that was fundamental to modern geology.

Lavoisier synthesized chemical experiments which before him had been performed haphazardly or unsystematically into theories that became the foundation of modern chemistry. In this book principles and nomenclature which form an inseparable part of that science are set down with admirable clarity and logic.

Jenner recorded in this book his momentous discovery of inoculation as a defense against smallpox.

Laplace's brilliant exposition of the stability of the solar system was presented in the five volumes of this great work, the culmination of a lifetime of mathematical research. The Lilly copy is among the finest known and is accompanied by a fine presentation copy of the great translation by the American Nathaniel Bowditch.

Dalton in these three volumes converted the vague atomic theory of the Greeks into a systematic scientific theory which led ultimately to our atomic age. The Lilly copy is complete and in unsurpassably fine condition.

This is the first appearance of Ampère's great paper in which he recorded his remarkable experimental investigations into electric currents. Ampère's brilliant results became essential to the development of electrodynamics.

Gauss' brilliant mathematical achievements can match those of any age. The section left out of his monumental Disquisitiones Arithmeticae (Leipzig, 1801) was first printed in these two parts, the second of which contains the first presentation of the square mot of minus one, a concept which has plagued math students ever since.

Faraday, the first to discover a way to generate electricity by means of magnetism, introduced in these papers the modern terminology of his subject. The importance of his researches and experiments to the later development of electrochemistry and modern atomic science can hardly be overestimated.

Using a living person whose stomach wound had healed but for a small opening, Beaumont conducted a study of digestion which ranks as one of the pioneer works of medical research in America. This copy of the results of that research is one of the very few presentation copies extant. It is accompanied by The Medical Recorder, Vol. VIII, Philadelphia, 1825, which contains, wrongly attributed to Joseph Lovell, Beaumont’s first published paper on the experiment.

This is the first medical work published in the state of Indiana. Selman was something of a quack and an eccentric. With a "marvelous glass eye" and a pet wolf, he roamed the woods seeking herbs for remedies he prepared himself to treat the Indians. Of his strange little book there are only five recorded copies.

If Daguerre must share the distinction of having invented photography, he was at least the first to publish an account of that great discovery. The imprint on the title page varies, but this Susse Frères imprint is considered the first. This copy bears the bookplate of Vincent Chevalier, co-owner of a famous Paris optical shop in which Daguerre spent a good deal of time discussing cameras and lenses. It was Vincent's son Charles who introduced Daguerre and Niépce, "a partnership to which not only France but the whole world owes one of the most brilliant scientific inventions."

Schwann, starting with Hooke's undeveloped concept of the cell as the unit of plant structure, extended cellular formation to the elementary parts of all organisms, undoubtedly one of the greatest achievements in modern biology.

The results of Agassiz's ten years of investigation into glacial phenomena were published in these two volumes, one of text and one of plates. By careful research he was able to show that Switzerland had once been covered by a great ice sheet. This conclusion he extended to include all areas where unstratified gravel is found.

Helmholtz's remarkable paper on the conservation of force ranks him as one of the founders of the law of the conservation of energy. Read first before the Physical Society of Berlin, it was published separately the same year and has since become quite scarce.

One of the most important subjects treated in this first classic of modern oceanography was the route of ocean currents. Maury attained an extensive knowledge of currents by studying the reports of sea captains presented to him in the form of an abstract log he himself had drawn up. An unused copy of that scarce log is also displayed here.

Knowledge of Virchow's pioneering work in cellular pathology became an absolute prerequisite for all who were to follow him in the development of that science. His book on the subject ranks among the most important ever produced in the medical sciences.

Pasteur presented this copy of one of his early and fundamental works on fermentation to Armand Fizeau, eminent French physicist, who had just become a member of the French Academy.

Gibbs, one of America's most brilliant scientists, developed in this great memoir principles which were to prove basic to the development of physical chemistry and thermodynamic theory.

In this work Koch, whose researches into bacteriology produced some of the most brilliant results of his time, established bacteria as the cause of many infections in wounds.

This off-print from the Sitzungsberichten der Würzburger Physik-medic. Gesselschaft contains the first publication of Röntgen's discovery of the X ray. The second part was issued the following year. Our copy of the first part is the earliest issue, with the price of fifty pfennig, which in later issues changed to sixty.

For her brilliant work in the investigation of radium, published complete for the first time in her Thèse, Madame Curie received not only the degree so essential to her continued research but, in 1903, the Nobel Prize in physics.

This is the first paper by Banting on the isolation of insulin, an achievement for which he won in 1925 the Nobel Prize. Banting's acceptance lecture delivered in Stockholm is also shown, a copy inscribed to Mr. J. K. Lilly. The Lilly company has been intimately associated with the production of insulin front the beginning.