New Experiments physico-mechanical, touching the Spring of the Air, and its Effects; A Defence of the Doctrine touching the Spring and Weight of the Air ... against the objections of Franciscus Linus; An Examen of Mr. T Hobbes his Dialogus Physicus de naturci aeris.

Oxford: H. Hall for T. Robinson [and London: J.G. for Thomas Robinson], 1662.

Second edition, containing the first announcement of Boyle’s law. This second edition is “particularly important for what Boyle called an ‘hypothesis’ but what we know as ‘Boyle’s Law’: that the volume of air in a confined space varies inversely as the pressure. He demonstrated this by much experimental detail: with experiments on rarefaction performed by others, including Hooke, and on compression performed by himself” (PMM). Boyle’s law is stated in the second part of this edition, his Defence against the attacks of Linus on the first edition of this work (1660). “In the first edition of the New Experiments (1660), Boyle had published his experiments proving that (1) air has weight and exerts pressure; (2) the phenomena associated with suction pumps and siphoning are caused by the evacuation of air; (3) air is necessary for life, flame and the transmission of sound; and (4) air is permanently elastic. These statements were attacked by many critics, whom Boyle refuted in an appendix to the second edition, a chapter of which describes the experimental attempts to measure atmospheric pressure that led to the formulation of Boylc’s Law” (Norman).

“Boyle had long been interested in the air, partly in connection with the Oxford physiologists’ concern with the nature of respiration, and partly because of the extent to which air might account for phenomena like solidification, which he had observed in ‘The History of Fluidity and Firmness’ in Certain Physiological Essays. Hence he was intrigued by Otto von Guericke’s use, in Germany, of a pump comprising a cylinder and a piston for the evacuation of copper spheres: these trials suggested how one might produce a larger vacuum chamber than seemed possible from the deployment of the space which was left when a mercury column fell due to atmospheric pressure, as demonstrated in a famous experiment by the Italian savant Evangelista Torricelli. Guericke’s own apparatus proved defective from Boyle’s point of view, since the receiver was opaque and hence nothing could be inserted in it and observed under experimental conditions; nevertheless this apparatus inspired him to commission the production of an improved design, first from the London instrument-maker Ralph Greatorex and then from his own assistant, Robert Hooke. Greatorex failed but Hooke brilliantly succeeded, illustrating the extraordinarily inventive talent he was to display for the rest of his career. Early in 1659, Hooke produced an apparatus comprising a brass cylinder with milled valves mounted on a wooden frame. Above this was a glass globe with an opening at the top which could be sealed as required; thus it made it possible to insert objects into the receiver (as it was called) and to examine the effect on them of the withdrawal of air, which was carried out by cranking the valved cylinder. By using this instrument with Hooke’s help, Boyle carried out his epoch-making experiments on the nature of air, mainly at Oxford in the spring, summer and autumn of 1659.

“Boyle carried out some forty-three experiments, the narratives of which were included in his published book [New Experiments Physico-Mechanicall, Touching The Spring and Weight of the Air, London, 1660]. Some of them were fairly straightforward, others less so, but all were striking for their vivid demonstration of the physical properties of air. They also illustrate Boyle’s extraordinary ingenuity in devising trials which would reveal significant information about the phenomena under scrutiny, which we have already encountered. The most important of the experiments, to which a substantial part of the book was devoted, were those which demonstrated that air might have a ‘spring’ — an idea which had been canvassed earlier in the seventeenth century but had never been proved. Many of Boyle’s experiments showed the capacity of air to exert pressure and to expand: for instance, when a vial partially filled with water was placed in the receiver and the air around it pumped out, the vessel exploded, cracking the receiver itself. Other experiments showed the extent to which diverse phenomena were dependent on air. When a Torricellian barometer was sealed in the receiver and the air evacuated, the level of the mercury fell, as Boyle illustrated to various of his Oxford colleagues. Sound failed to travel through the evacuated receiver, and combustion was extinguished in it.

“Each of these findings was painstakingly expounded in the book, and Boyle also devoted ‘digressions’ to various issues, for instance ‘whether or no Air may be generated anew’, while towards the end of the work there was a lengthy excursus on respiration and the role of air in relation to it, reflecting the interest in this topic of members of the Oxford group earlier in the 1650s. Boyle did not pretend that all of the phenomena that he observed were easily explicable, and much space was devoted to analysing them and to expounding the theories of previous authors who had considered such phenomena and their explanation — especially French natural philosophers like Pierre Gassendi, Rene Descartes, Marin Mersenne, Jean Pecquet, Gilles Personne de Roberval and Blaise Pascal. In addition, at every point Boyle considered Aristotelian theories about the nature of the air, and particularly scholastic explanations based on the view that nature abhorred a vacuum and hence that many of the phenomena he observed were the result of nature’s attempts to prevent such an outcome. The result was one of the most seminal and innovative works of the scientific revolution. As the Halifax natural philosopher Henry Power put it: ‘I never read any such Tractate in all my life, wherein all things are so curiously and critically handled, the Experiments so judiciously and accurately tried, and so candidly and intelligibly delivered’ …

“The most significant institution with which Boyle became associated at this point was the Royal Society, the first public institution devoted to the pursuit of scientific research, which was consciously ‘established’ in 1660 with aspirations to permanence and was to go on to become the premier institution of British science. An important role in founding the society was played by men with whom Boyle had been associated at Oxford in the 1650s, including John Wilkins (who had moved to Cambridge in 1659 and had become Dean of Ripon in 1660); also important were members of the royal court such as Viscount Brouncker and Sir Robert Moray. Boyle himself played an inspirational role through his writings, notably his recently published New Experiments Touching the Spring of the Air, which seemed to exemplify the experimental philosophy to which the new body was devoted.

“The Royal Society’s inaugural meeting took place on 28 November 1660 at Gresham College, an educational institution in the City of London founded in the Elizabethan period, following a lecture by Christopher Wren, by then Professor of Astronomy there. Boyle was in attendance on this occasion and he was at many of the society's early meetings, though the fact that his main place of residence continued to be Oxford meant that he played a less central role in the institutional life of the society than its London based fellows. In view of the fact that New Experiments had appeared only a few months earlier, it is hardly surprising to find Boyle being asked to demonstrate pneumatic experiments at various meetings of the society in the early months of 1661, and on 15 May 1661 he presented the society with an air-pump. Indeed, the gadget became something of an emblem of the society and of the enterprise to which it was devoted, and its symbolic significance is illustrated by the fact that a modified version of it is depicted on the frontispiece of Thomas Sprat's promotional History of the Royal Society, begun in 1664 and published in 1667 — a work consciously intended to promote the new body and the ends for which it had been founded.

“The import of the association with the air-pump for the Royal Society — and for Boyle — became all the clearer during 1661, when various books were published commenting on New Experiments, hence adding to its notoriety. One such book was written by Boyle’s own assistant, Robert Hooke: An Attempt for the Explication of the Phaenomena, Observable in an Experiment Published by the Honourable Robert Boyle, Esq. This was a kind of gloss on Boyle's work which offered an explanation of capillary action as observed in experiment 35 there. More troubling were two books which made an outright assault on the claims Boyle had put forward: Thomas Hobbes’ Physical Dialogue, or a Conjecture about the Nature of the Air taken up from the Experiments recently made in London at Gresham College, published in August 1661, and Francis Linus' Treatise on the Inseparable Nature of Bodies, published in the same year, in which, as its subtitle promised, ‘the vacuum experiments of Torricelli, von Guericke and Boyle are examined, their true explanations given, and consequently it is shown that a vacuum cannot be produced naturally, and so Aristotle's teaching on rarefaction is upheld.’ Boyle seems quickly to have felt the need to respond to the challenge which these books presented — to him and, as Hobbes’ title showed, by extension, to the Royal Society. In October 1661, he therefore set to work on replies to them, which were published as a combined volume in 1662, in conjunction with a second edition of his original book in a new, matching format.

“Like Boyle, we will deal with the two critiques separately, starting with that of Linus. Linus was an English Jesuit who had spent many years teaching at the English College of Liège, although by this time he had returned to England. He was a committed Aristotelian, and the thrust of his book was to defend the Aristotelian axiom that nature abhors a vacuum. But, like many Jesuit scientists, he had a keen interest in experiment, commenting at length on Boyle’s and recounting his own attempt to replicate the famous trial made by Florin Périer at the behest of Blaise Pascal in 1648, when he took a barometer up a mountain and observed its changed behaviour at an increased altitude. On the other hand, the conclusions he drew from the phenomena observed were resolutely Aristotelian, the most novel being that there was a kind of invisible thread or ‘funiculus’ which occupied the space above the mercury column in a barometer and accounted for the recorded effects. Boyle’s response, entitled A Defence of the Doctrine Touching the Spring and Weight of the Air … Against the Objections of Franciscus Linus, Wherewith the Objector’s Funicular Hypothesis is also Examin'd, was polite but firm; it praised Linus for his interest in experiments but insisted that defects in his actual experimental practice negated the conclusions he drew from them, particularly Linus’ funicular hypothesis as against Boyle's mechanistic one. Boyle also adduced new findings which, he claimed, reinforced his original claims, particularly by using a J-shaped tube in conjunction with a long pipette to illustrate the correlation between the compression and rarefaction of air and its volume, demonstrating (in his own words) that ‘the pressures and expansions [are] in reciprocal proportion’ — in other words that the relationship between the volume of air and the pressure it is under is a constant. This relation has long been known as Boyle's Law.

“This claim, adumbrated for the first time in Defence (on the basis of a table of findings presented to the Royal Society on 2 October 1661), has been the subject of much controversy. In formulating it, Boyle drew on experiments on related topics carried out by the natural philosophers Richard Towneley and Henry Power in the north of England, which he duly acknowledged although rightly taking the credit for the claim he made on their basis. In addition, his own findings undoubtedly owed much to his assistant Robert Hooke, who was in fact the author of a whole section of the book — the appended ‘Explication of Rarefaction’ — though through a printer’s error he failed to be given due credit for it; Boyle pointed out this fact to the Dutch natural philosopher Christiaan Huygens and to others interested in the matter. On balance, it seems right that the law should be attributed to Boyle. Since Towneley and Power had failed to draw out the implications of their initial findings, Boyle legitimately felt that the matter needed to be further investigated before a definitive conclusion could be reached. As for Hooke, he was of course working as Boyle’s assistant at the time, but there is no reason to doubt that the error over the attribution of ‘An Explication of Rarefaction’ really was the printer’s — had it not been for that, Hooke would effectively have been presented as Boyle’s co-author — and there seems little doubt that Boyle already regarded Hooke as intellectually his equal, if not his superior in some respects. Yet here, too, there seems no doubt that Boyle was the one who inspired and supervised the exercise as a whole” (Hunter, Boyle, pp. 124-134).

Dibner Heralds of Science 142; Evans 28; Grolier/Horblit 15; PMM 143; Norman 300; Fulton 14.

4to (197 x 147 mm), pp. [xvi], 207, [1], [12], 122, [2], [8], 86, [2], 85-98 [2:blank], 2 engraved plates (one folding: re-hinged and supplied from another copy),

Item #4154

Price: $25,000.00