138 



THE ROTARY PROPERTIES OF 



The weighted mean of the last column but one gives 



(a) D = -38.7, 

 with a probable error of less than half a degree. 



SodiumrcJdoride-potasiium-hydroxide Solution. 



A remnant of Solution 15 (diluted), containing 90 cubic 

 centimeters, was made up in a graduated flask to 100 cubic 

 centimeters with an 8 per cent potassium-hydroxide solu- 

 tion. The solution thus formed contained, in 100 cubic 

 centimeters, 0.85 gram of flax-seed globulin, 9 grams of sodium 

 chloride, and 0.8 gram of potassium hydroxide. 



The color of the solution was changed by the potassium 

 hydroxide from a bright yellow to an orange tint, which made 

 it more difficult to measure the rotation, even with a 100- 

 millimeter tube. As a result of four measurements with a 

 100-millimeter tube at the temperature of 23 C., the rotation 

 of the plane of polarization was found to be 0.464 0.013. 

 This would give as the specific rotation of flax-seed globulin 

 in such an alkaline solution, 



(a) D = -64.5 1.5 C 



