LIFE: ITS ORIGIN AND NATURE > 57 
Prof. Sliiro Tashiro, of the University of Chi¬ 
cago, has shown that all living things give off 
carbon dioxide—even seeds which have been 
almost completely desiccated, and are many 
years old. As long as this gas is given off, the 
plant or animal is alive; but as soon as it is 
dead, this ceases. He has proposed in this 
experiment a new test for death—or for life! 
He is careful to point out, however, that this 
is merely a chemical sign, which is the result of 
life activities, and in no wise helps us to under¬ 
stand the nature of life itself. It is merely one 
of its phenomena or manifestations. 
The extraordinary difficulty which we ex¬ 
perience in telling when a thing is alive and 
when it is dead is also illustrated by experi¬ 
ments conducted at the Rockefeller Institute, 
in New York, in which a fragment of a 
chicken’s heart has been kept alive for several 
years,— and is even yet healthy and growing 
actively! For a number of days, this fragment 
of heart pulsated; these pulsations gradually 
ceased, but the fragment continued to live and 
grow. Certain salt-solutions, in which the 
tissue was immersed, rendered this possible. 
Here is a very extraordinary fact, and has 
naturally given rise to much speculation as to 
the role which certain solutions of salts may 
play in the human economy. Loeb and others 
have written extensively upon this subject. 
The recent experiments in “grafting glands,” 
and thereby effecting a certain apparent re¬ 
juvenation in the subject, are also thought-pro¬ 
voking; for to what extent are health and youth 
dependent upon the secretions of these glands? 
