Laking of Blood by Hypertonic Solutions. 149 



47 mm. Hg pressure. The average specific gravity of the first 

 sample was 1.059; an d of the last 1.056. The average change in 

 freezing point was + 0.016. 



Viscosity measurements were made in a few experiments. In 

 this respect also there was insufficient evidence for attributing 

 the clinical condition of the animal to mechanical change in the 

 blood. 



91 (908) 



Laking of blood by hypertonic solutions. 



By C. C. Guthrie and M. E. Lee (by invitation). 



[From the Physiological Laboratory, University of Pittsburgh.] 

 It is known that hypertonic solutions when added to blood 

 may cause laking. 1 To determine if possible if this phenomenon 

 could be due to a drying action on the scarlet blood discs, as this 

 is known to so affect them that they lose hemoglobin to watery 

 solutions even though such solutions are iso- or hyper-tonic to 

 blood serum, experiments were performed to observe the action of 

 hypertonic solutions of a number of relatively inert inorganic 

 salts and other substances, including the chlorides of Na, K, Mg, 

 Ca and Ba; the sulphates of Na, K, Mg; cane sugar and glycerine. 

 For in drying through evaporation the salt content of the liquid 

 surrounding the cells must become decidedly concentrated before 

 all of the water has evaporated. The results of the observations 

 may be summarized as follows: 



1. Laking by hypertonic sodium chloride solutions or by 

 hypertonic solutions of other inert salts is proportional to the 

 concentration of the solution. 



2. In hypertonic solutions of inert substances in equimolecular 

 concentrations, laking is not the same in all. And consideration 

 of the isotonic coefficients of such substances does not indicate 

 that laking is altogether due to osmotic strength. 



3. In equimolecular hypertonic concentrations, the chlorine 

 salts are more powerful than the corresponding sulphates. 



4. Non-electrolytic solutions, as cane sugar and glycerine, in 

 hypertonic concentration produce laking, and it is proportional to 

 the concentration of the solution. 



1 Bursy, Inaugural-Dissertation, Dorpat, 1863. 



