Expressed Plant Tissue Fluids. 



357 



of the whitest possible patent flour for human consumption, and 

 the clear grades of flour, although they contain no shorts or bran, 

 are too yellow in color for the American market. They contain 

 much more phosphate than patent flour. The grain itself varies 

 in phosphate content. Lack of available phosphate in the soil, 

 or certain climatic conditions, may cause a reduction of phosphate 

 content of grain. D. C. Mebane and myself showed that on a 

 diet containing 45 per cent, of low phosphate rye (grown on peat 

 soil) rickets was produced in white rats, whereas if this was sub- 

 stituted by high phosphate rye (from peat land in which the soil 

 phosphate was made available by burning) no rickets developed. 

 Soft winter wheat from the Ohio valley may be low in phosphate, 

 and patent flour made from this wheat may contain as low as 

 0.075 P er cent. P. Such flour was used in making a diet for white 

 rats and produced severe rickets, whereas patent flour from hard 

 spring wheat produced milder rickets, and Graham flour, no 

 rickets. The percentage of phosphate in the patent flour depends, 

 however, on the process of milling. At the Minnesota State Flour 

 Mill some patent flour was made from the third middlings and 

 contained 0.072 per cent. P, whereas the second clear flour con- 

 tained 0.297 per cent. P. This, together with Graham flour, 

 which I made by grinding hard winter tempered wheat containing 

 3-55 P er cent. P, was used in making the following diets: Diet 

 96 — NaCl 2 per cent., plaster of paris 2 per cent., yeast 1 per cent., 

 spinach 1 per cent., lactalbumin 10 per cent., cotton seed oil 20 

 per cent., low phosphate flour 54 per cent., NaHC0 3 10 per cent. 

 Diet 98 was the same except there was no NaHCOs and the flour 

 was 64 per cent. Diet 99 was the same as diet 98 except the 

 second clear flour was used. Diet 100 was the same except that 

 Graham flour was used. 



Diet. 





96 



98 



99 



100 





O.I20 



0.133 



0.287 



0.340 





0.607 



0.621 



0.645 



0.63s 



