26 THE BEGINNINGS OF LIFE. 



school treatises like Dr. Lionel Beale's book on Protoplasm. We 

 find life constantly standing in relation to the physical forces. 

 It does work, and in doing it uses up the protoplasmic material, 

 which has to be renewed by the assimilation of other protoplasm, 

 as in animals, or the metabolism of inorganic matter, as in 

 plants. It is manifested in conjunction with other forms of 

 energy, heat, light, and electricity, and seems to stand in the 

 same category as they. Indeed, as the suggestive experiments of 

 a German biologist, Professor Biitschli, have shown, the work 

 which the protoplasm does in the movements of the amoeba may 

 be imitated mechanically. He prepared frothy mixtures of oil 

 with certain chemical substances, chiefly olive oil and finely 

 powdered potassic carbonate, which makes a soapy foam. Tiny 

 drops of this emulsion introduced into water, and viewed under 

 the microscope, are found to be filled with vacuoles, and to 

 exhibit, for as long a period as six days after their preparation, 

 the streaming, diffluent movements of the amoeba, and, like the 

 amoeba, put out and draw in processes, or pseudopodia, and creep 

 across the glass. But remembering the vast complexity of 

 protoplasm, and the comparative simplicity of the oil-foam, we 

 must suspend our judgment as to whether the movements of the 

 amoeba are purely mechanical. The striking correspondence 

 shown by Professor Biitschli may be more apparent than real. 

 Still, the whole tendency of scientific thought favours the 

 mechanical theory of life, and if anyone should collate these 

 considerations with the further one that the soul of man is but a 

 name we have given to the sum total of his consciousness, and 

 should feel pain or alarm in consequence, we can only remind 

 him for his comfort that what we know is but an insignificant 

 fraction of the vast unknown and unknowable. In that dark 

 region there is room for boundless possibilities, boundless hope. 



[The diagrams and photomicrographs with which this 

 lecture was illustrated will be reproduced in a future Volume of 

 the Proceedings.] 



