"CLEARLY RECOGNIZED THAT WATER VAPOR INTERCEPTED TERRESTRIAL RADIATION, AND THAT CHANGES IN ITS QUANTITY WOULD PRODUCE (AND HAD PROBABLY CAUSED) CLIMATIC CHANGES": JOHN TYNDALL'S LANDMARK 1861-62 BAKERIAN LECTURE, "ON THE ABSORPTION AND RADIATION OF HEAT BY GASES AND VAPORS," EXPERIMENTALLY DEMONSTRATING WHAT WE NOW CALL THE GREENHOUSE EFFECT

TYNDALL, John. The Bakerian Lecture: On the Absorption and Radiation of Heat by Gases and Vapours, and on the Physical Connexion of Radiation, Absorption, and Conduction. London: Taylor and Francis, 1861-62. Quarto, modern marbled paper wrappers. Housed in a custom clamshell box. $2000.

First appearance of both parts of Tyndall's important paper on heat absorption and radiation—describing and experimentally demonstrating what we would now call "the Greenhouse Effect"—extracted from the journal Philosophical Transactions where they originally appeared, with the volume title pages from that journal and the two engraved plates that accompanied this paper.

"Tyndall's most important contribution to physics, begun in 1859, concerned radiant heat in its relation to gases and vapors. He was led from the consideration of the origin and continued existence of glaciers to investigate the part played by water vapor and other constituents of the atmosphere in producing the low temperatures which prevail in mountainous regions. Prior to 1859 no means had been found of determining by experiment, as Macedonio Melloni had done for solids and liquids, the absorption, radiation, and transmission of infra-red radiation by gases and vapors. Realizing that the effects were probably small Tyndall devised an arrangement of galvanometers and thermopiles that measured absorption differentially, using an empty test-tube as a null balance point. Unexpectedly he found that while elementary gases offered practically no obstacle to the passage of infra-red, some of the compound gases absorbed more than 80 per cent of the incident radiation. Allotropic elements came under the same rule, ozone for example being a much better absorbent of heat than oxygen. The temperature of the source of heat was found to be of importance: heat of a higher temperature was much more penetrative than heat of a lower temperature… Tyndall also clearly recognized that water vapor intercepted terrestrial radiation, and that changes in its quantity would produce (and had probably caused) climatic changes… Much of this work was reported in two Bakerian lectures (1861 [the present paper], 1864) and led to the award of the Rumford medal in 1869" (ODNB).

"Glaciers fostered a passion for mountaineering and a fascination for what was to become his major work—the effects of solar and, later, heat radiation on atmospheric gases (1860-70). He then considered the scattering of light particles in the atmosphere (the 'Tyndall effect') and explained the blue color of the sky ('Rayleigh scattering')" (DSB). "The intense heat of the sun's direct rays on high mountains is not, I believe, due to his beams having to penetrate only a small depth of air, but to the comparative absence of aqueous vapor at those great elevations. But this aqueous vapor, which exercises such a destructive action on the obscure rays, is comparatively transparent to the rays of light. Hence the differential action, as regards the heat coming from the sun to the earth, and that radiated from the earth into space, is vastly augmented by the aqueous vapor of the atmosphere" (Vol. 151, p. 28). "As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown as a dam across the terrestrial rays, produces a local heightening of the temperature at the earth's surface. This, of course, does not imply indefinite accumulation any more than the river dam does" (Vol. 152, p. 95). "I satisfied myself… that ozone had a power of absorption very much greater than common oxygen" (Vol. 152, p. 61). With title pages of the two volumes of Philosophical Transactions from which these papers were extracted, along with the two engraved plates that accompanied them (actually a duplicate image, but a year separated the publication of the two parts of this paper).

Fine condition.