118 Transactions. — Miscellaneous. 



modes of molecular motion — first, the locomotion and cyclosis of animal 

 and vegetable cells, and, second, the chemical motion of combination and 

 dissociation of elements. For chemical combination is merely a molecular 

 motion of the combining elements. When hydrogen and oxygen are mixed 

 in a vessel, they may remain in contact for an indefinite time — but if an 

 electric spark or a lighted taper is applied, they immediately rush together 

 and form water. But the force which produces this sudden activity is 

 merely matter in motion, which imparts its own vibrations to the hydrogen 

 and oxygen, and thus produces their union. The application of electricity 

 in the form of a galvanic current, by producing a different form of motion, 

 separates the elements again, shakes them asunder as it were, into 

 hydrogen and oxygen, which may be collected in separate vessels. Thus 

 the latent life of a seed or an egg is analogous to the chemical affinity of 

 hydiogen and oxygen — the tendency to active vitality is there, but requires 

 an appropriate stimulus to call it into action. This stimulus is heat in due 

 proportion, which is, like the burning taper or the electric spark, only 

 matter in motion, and in such form of motion that it is capable of com- 

 municating it to the hitherto inert protoplasm. 



A most interesting series of experiments has been made by Dr. Siemens, 

 the result of which he communicated to the Koyal Society in March last. You 

 all know that plants only form that green colouring matter termed chlorophyl 

 under the influence of sun-light, and that chlorophyl performs its special 

 fvmction, that of decomposing carbonic acid, in the day-time. Plants kept 

 in darkness are blanched, and during the night the evolution of oxygen by 

 them ceases. Dr. Siemens has, however, shown that the electric lamp can 

 take the place of the sun, and that under its light plants will develope 

 chlorophyl, dissociate the elements of carbonic acid, and evolve oxygen, the 

 same as when exposed to direct solar influence. Here, then, we have the 

 cycle of the vital physical forces complete. Heat is converted into light and 

 electricity — light is converted into heat and electricity — electricity is con- 

 verted into heat and light. For not only does the chlorophyllian action 

 continue under the influence of the electric lamp, but seeds will germinate, 

 and plants grow, and produce those starches and sugars which are in reality 

 the great deposits from which animals derive their heat. 



Again, many animals possess the power of emitting light, and this 

 faculty appears to exist in some cases in connection with muscular action, 

 in others with nervous influence ; in others again a special apparatus of 

 photogenic cells exists, and these cells seem invariably to be in intimate re- 

 lation with the nervous system. Whilst in one class, which is not endowed 

 with a nervous system, the luminosity appears to be the result of some un- 

 known property of the protoplasm of the phosphorescent being. 



