II. 



Artificial Protoplasm/ 



LET it be said at once, for the benefit of the timid, that Professor 

 Biitschh does not claim to have made protoplasm. His 

 sumptuous quarto contains the results of ten years' special 

 work on the physical side of the phenomena of life. The author is 

 very strongly opposed to that school of Biologists who attempt to 

 surround the phenomena of life with unnecessary mystery, and who 

 clamour at once timidly and virulently against all physical and 

 chemical interpretations. He has now been able to make microscopic 

 foams which in structure and behaviour, under various conditions, 

 marvellously resemble the structure and behaviour of protoplasm. 

 These foams have enabled him to bring together the observations of 

 himself and others on the actual structure of protoplasm, and to 

 furnish a striking theory of its physical nature. 



He tells us that he began his attempts at the making of foams 

 with the forlorn feelings of a nineteenth century alchemist. The 

 starting point was this : If fine particles of a substance soluble in 

 water be mixed with a fatty oil, and the mixture be placed in water, 

 the water diffusing into the oil becomes arranged in minute droplets 

 round the particles of soluble material, and a foam is formed. 

 Owing to the difficulty of breaking up the soluble substance into 

 sufficiently minute particles, the particles, viewed under the micro- 

 scope, are very coarse. The drops are placed on the under side of a 

 coverslip with wax feet, and the coverslip is placed in a drop of water 

 on a slide. When such a slide is put in a damp chamber for about 

 24 hours, the drop becomes quite milky and opaque. When it is 

 flattened out by pressing on the coverslip, or made transparent by 

 allowing glycerine to diffuse through it, this drop shows that it is 

 composed of a very fine froth. It seems probable that the froth is 

 caused by the presence in the oil of a small quantity of soap. 

 The soap is more soluble in water, and the solution of soap and 

 water has gradually separated out in very fine droplets. Biitschli 

 empirically found the best way to produce these froths. Fresh olive 



1 UnTERSUCHUNGEN UEBER MlKROSKOPISCHE SCHAEUME UND DAs'PrOTOPLASMA. 



By O. Biitschli. (With 6 lithographic tables, and 23 figures in the text.) Leipzig: 

 Engelmann, 1892. Price 24 marks. 



