46 
Walter Stiles snd Ingvar J orgensen. 
50 IOO ISO 2-°° 
Time in hours. 
Fig. 2. Change in weight of red beet-root during immersion in distilled 
water and sodium chloride solutions of different concentrations. 
special precautions were taken to keep the liquids sterile, although 
the solutions were renewed daily. How far therefore the shrinkage 
which ultimately supervenes, and which is one of the features of 
death of the tissue, is due directly to the action of the salt on the 
tissue or to the secondary action of micro-organisms cannot be 
said. It can at any rate be concluded that the tissue remained 
in approximate equilibrium with distilled water up to the 200th 
hour of immersion, with 0-125 N and 0-40 N and 0-45JN up to the 
100th hour of immersion, and with 0-25 N up to about the 300th 
hour of immersion (see Table 1). These times are all minimum 
values. The longer resistance to injury in the case of 0-25 N 
sodium chloride may be simply accidental in this instance; if 
not it might he explained on the ground that in the concentrations 
higher than this the injurious action of the salt comes into 
evidence sooner, while diluter solutions do not inhibit the injurious 
action of micro-organisms. It is clear in any case that beet-root 
