﻿PHYSICAL PROPERTIES OF SOME TOXIC SOLUTIONS 



George B. Rigg, H. L. Trumbull, and 



This paper deals with the osmotic pressure and the surface ten- 

 sion of (i) water obtained from sphagnum bogs of the Puget Sound 

 region and Alaska, (2) solutions obtained by allowing the rhizomes 

 of Nymphaea polysepala Gr. to decay in water. 



Osmotic pressure 



The difference between the freezing point of each solution and 

 that of pure water was determined with the Beckman apparatus. 

 From this lowering, the osmotic pressure at o° C. was calculated in 

 two ways: (1) from a consideration of the relation between molar 

 concentration and osmotic pressure 1 established directly by 

 Morse (6) ; (2) by substitution in the ordinary formula based on 

 thermodynamic reasoning, namely, P=i2.o$Xdt atmospheres 

 at o°. 



In table I, dt represents the lowering of the freezing point in 

 degrees centigrade; M represents the molar concentration of a 

 solution of any non-electrolyte which shows the same lowering of 

 the freezing point; P represents the osmotic pressure in millimeters 



k 1 These investigators found that o . 1 M sugar solutions at o° C. give 2 . 462 atmos- 

 Botanical Gazette, vol. 61] [408 



