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according acid action active actual admit agents amount animal appear applied arguments attraction Beale becomes blood body called carbonic cause cell chemical chemical affinity coagulation combination complete compounds considered constitution contain dead death definition depend difficulty direct discovery distinct effect elements essential exactly exist explain expressions fact faculty fall fibrin Fletcher fluid force formation germinal give given gravity heat idea important inherent irritability kind known laws light living matter mass material means merely motion muscle muscular myosin nature never ordinary organic organised origin oxygen pabulum particles phenomena physical possessed potential energy present probably produced properties protoplasm proximate principles purely question reason remains respect result says sense separated simply speaks stimuli substance supposed take place term theory thing tion tissue true vital vital action vital principle weight whole
Pàgina 95 - That gravity should be innate, inherent, and essential to matter, so that one body may act upon another at a distance through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an. absurdity, that I believe no man who has in philosophical! matters a competent faculty of thinking, can ever fall into it.
Pàgina 89 - ... chemical force. The beautiful experiments of Seebeck and Peltier show the convertibility of heat and electricity ; and others by Oersted and myself show the convertibility of electricity and magnetism. But in no case, not even in those of the Gymnotus and Torpedo, is there a pure creation or a production of power without a corresponding exhaustion of something to supply it.
Pàgina 92 - A particle of oxygen is ever a particle of oxygen— nothing can in the least wear it. If it enters into combination and disappears as oxygen — -if it pass through a thousand combinations, animal, vegetable, mineral—if it lie hid for a thousand years and then be evolved, it is oxygen with its first qualities, neither more nor less.
Pàgina 178 - The pabulum does not shade by imperceptible gradations into the living matter, and this latter into the formed material, but the passage from one state into the other is sudden and abrupt, although there may be much living matter mixed with little lifeless matter, or vice versa.
Pàgina 169 - Biology has come into common use, it seems desirable to employ the same root in designating the matter which it is the main purpose of biology to investigate. Bioplasm involves no theory as regards the nature or the origin of the matter. It simply distinguishes it as living. A living white bloodcorpuscle is a mass of bioplasm, or it might be termed a bioplast. A very minute living particle is a bioplast, and we may speak of living matter as bioplasmic substance.
Pàgina 92 - What is called chemical attraction affords equally instructive and suggestive considerations in relation to the principle of the conservation of force. The indestructibility of individual matter is one case, and a most important one, of the conservation of chemical force. A molecule has been endowed with powers which give rise in it to various qualities, and these never change, either in their nature or amount. A particle of oxygen is ever a particle of oxygen — nothing can in the least wear it....
Pàgina 171 - nucleus and cell contents"; in others to the matter lying between the "cell wall," and certain of the "cell contents": while the formed material in some cases corresponds exactly to the "cell wall" only; in others to the "cell wall...
Pàgina 119 - ... yet be drawn from observation. But the manifestations of this power presuppose another faculty of the cells. The cytoblastema, in which the cells are formed, contains the elements of the materials of which the cell is composed, but in other combinations : it is not a mere solution of cell-material, but it contains only certain organic substances in solution. The cells, therefore, not only attract materials from out of the cytoblastema, but they must have the faculty of producing chemical changes...
Pàgina 92 - If it enters into combination and disappears as oxygen — if it pass through a thousand combinations, animal, vegetable, mineral — if it lie hid for a thousand years and then be evolved — it is oxygen, with its first qualities, neither more nor less. It has all its original force, and only that ; the amount of force which it disengaged when hiding itself has again to be employed in a reverse direction, when it is set at liberty...
Pàgina 188 - When we look carefully into the question, however, we find that what the germ really supplies is not the force, but the directive agency ; thus rather resembling the control exercised by the superintendent builder, who is charged with working out the design of the architect, than the bodily force of the workmen who labour under his guidance in the construction of the fabric.