THE ANIMAL A MACHINE 185 



is a unit of life in the same sense as the legs or arms are 

 units of life, since they are parts of a living human body. 

 It should also be remembered that there are living things- 

 the viruses — so small that they cannot consist of cells at 

 all, since they consist of only a single molecule, to use the 

 language of the chemist. Hence there are cases in which 

 the unit of life, if there is any, is much smaller than the cell. 



Moreover cells, or at least what looks like them, can be 

 found also in non-living matter. The "autosynthetic cells" 

 and the "colpoids" are by no means the only representatives 

 of artificial cells. The old artificial cells of Traube, bags of 

 a gelatin precipitate, have already been mentioned. Any or 

 all of the artificial osmotic structures may also be designated 

 as artificial cells, or perhaps, in some cases, as aggregates 

 of artificial cells. Each of these cells imitates some definite 

 feature of living cells. Each of these models is of value in 

 the interpretation of life phenomena. Thus Traube's cell 

 throws some light upon the origin and the importance of 

 the cell membrane, while the various oil-drop cells explain 

 cell movements and other features. 



These facts are not generally known. Any announce- 

 ment that artificial cells have been made may be hastily 

 seized upon as the dawning of a new era. This explains the 

 strange train of events which occurred early in 1931, when 

 a news reporter of the Chicago Tribune came into the re- 

 search laboratory of the Cleveland Clinic and took a look 

 through a microscope at one of those oil-drops from fresh 

 brain material. Not knowing what he saw, he believed it to 

 be artificial life or something near it. While under this 

 impression, he sent a red hot report to the Tribune, which 

 was rendered still more exciting by the reporter's statement 

 that he was the first layman to see this discovery and par- 

 ticularly that he did so without the proper permission of 

 the administration of the Clinic. The first statement ap- 

 pearing in the Tribune was nevertheless quite moderate and 

 authentic. But as the news spread to other papers, it 



