General physiology : an outline of the science of life / by Max Verworn, tr. from the 2d German ed. and edited by Frederic S. Lee. With two hundred and eighty-five illustrations.

  • Max Verworn
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: General physiology : an outline of the science of life / by Max Verworn, tr. from the 2d German ed. and edited by Frederic S. Lee. With two hundred and eighty-five illustrations. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    contributions to the physiology of the cell, and in our own time, from this side especially, the physiology of reproduction, fertili- sation, development, and heredity has been taken away from physiology proper, and developed into a fruitful and independent subject.^ The coitqxmdive method has not been employed in physiology since Johannes Mliller's time, unless the few researches that have been conducted upon other animals than the usual dogs, rabbits, and frogs are to be considered as comparative. Plant physiology, however, has developed quite independently into a flourishing science; and the distinguished labours of Hofmeister, Nageli, Sachs, Pfeffer, Strasburger, Berthold, and others have made this in recent times the most complete branch of physiology. This is due partly to the fact that all vital relations are much simpler and more easily surveyed in plants than in animals, and partly to the fact that plant phj'siology has made use of certain acquisitions of science that have thus far found little or no application to the physiology of animals. There are three of the greatest discoveries of this century, from the further e5q)ansion of which physiology is justified in still expecting great results. One of these is the law of the conservation of energy, which was definitely expressed by Robert Mayer (1814-1878), and Avas estab- lished most comprehensively by Helmholtz. Modern chemical investigations had led to a recognition of the lato <f the conservation of matter, by showing that the quantity of matter, of atoms, in the universe is constant, and that the smallest atom cannot by any agency bo destroyed or recreated. The law of the conservation of energy expresses the same fixedness for the sum of the energy of the universe. Energy, like matter, can be neither destroyed nor recreated; when it seems to appear or disappear, it merely passes from one form into another. Among the recognised forms of energy two varieties are distinguished : energy of motion, or kinetic energy, when power is in action, i.e. is pro- ducing motion; and energy of position, or potential emrgy, when it is latent but under certain conditions can come into action. Thus, e.g., the potential energy that was produced in the Carboniferous age by transformation of the kinetic energy of the sun's rays through the activity of plants and was stored up as chemical affinity in vast strata of coal, passes over into heat upon combustion of the coal. The heat is transformed by steam engines which are heated by the coal, into the energy of ' Resiimds of what has been accomplished in this field are given by the following books: Di<>. Zdh unci die Gewehe, by 0. Hei-twig (1892) [autliorised English trans- lation. The Cell: 0nfIinett of General Anatomy and Physiolo;/j/, 1895]; Gesammelte Ahhatidlnngen iiher EiitiricMnnrf-vnechanik; by W. Roux (189.5); La .'<trHc/u)-e dn j>rotoplasma et les thcoriea su7' I'hcrcdite, etc., by Yves Delage (1895) ; [and The Cell in Development and Inheritance, by E. B. Wilson (1896)].