On the rise of the sap in the spring / Edwin Sidney.

  • Sidney, Edwin, 1798?-1872.
Date:
1852
Catalogue details

Licence: Public Domain Mark

Credit: On the rise of the sap in the spring / Edwin Sidney. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    burnum and cambium being cut across, it at once diverged laterally. There was nothing to indicate a vertical descent, but, on the contrary the current by endosmose took the directions indicated by circum- stances. When also we consider the phenomena exhibited by cut- tings of plants turned upside downwards, -they indicate diffusion, according to the physical laws which have been considered, rather than such movements as have been so long attributed to currents of sap. If these facts be coupled with the proofs that may be given that the upward and downward channels so often taken for granted by vegetable physiologists have no ostensible existence, it must be allowed that the old theories, however fascinating, must give way, and the movements of the nutrient fluids be interpreted on sound principles. We shall be safe in speaking of the diffusion of these fluids as taking place according to the laws which have been demon- strated, and which must be considered as prevailing, not only as we know they do, in amorphous cellular masses, but in regularly or- ganized structures. The speaker concluded by apologizing for bringing this subject forward before such an audience, but his design was to excite to inquiry into the phenomena alluded to as amongst the most interesting that could occupy the attention. In the course of the evening there were also cited some experiments by the speaker on parts of plants in active growth with ozonometric tests, which mani- fested such actions as would consist with the idea that either ozone, or oxygen tending to act like ozone, was in some manner ])resent at the places tested. If so, these phenomena might tend to throw new and important light on the chemistry of vegetable life. [E. S.] In the Library were exhibited : — Casts of the Venus de Medicis, Venus of Melos, Apollo Belvedere, Laocoon, Dying Gladiator, Head of Jupiter, (reduced by Machinery). [Exhibited by R. Westmacott, Esq.] The Theseus and Ilyssus, — Machine Sculpture, by Mr. Cheverton. Bourdon’s Metallic Barometer and Steam-Gauge, with enlarged models. [Exhibited by Mr. Dewrance.] Model of Appold’s Self-regulating Friction-break,— Labour-Machine for Prisons. [Exhibited by J. G. Appold, Esq., M.R.L] A New Instrument for Drawing Ellipses, by Dr. Roxburgh, M.R.L Crystals of Sulphate of Quinidin; and Specimens of Cast Iron, Ancient and Modern. [Exhibited by T. N. R. Morson, Esq., M.R.L] Photograph Poi trait of Biot by M. Regnault. [Exhibited by Mr. Faraday.]