Phosphorus. 'ill 



said to be superior to cows" milk, which, though richer than 

 huuum in total P.2O5, has yei a lower percentage of organic 

 P2O, ((14) Siegfried). 



It is apparently a well-known fact that Australian cereals 

 are lower in phosphorus content than the cereals of other coun- 

 tries ; the general figure for wheat varies from 0.65 to 1.1 1 per 

 cent. P2O5 in other countries, whereas 0.5 per cent, is taken as the 

 average figure for Australian w^heat ; and likewise for oats ; 

 which fact points to an adaptation on the part of cereals to 

 phosphorus-poor soils. From a physiological point of view it is 

 the edible flour made from the wheat which is the most im- 

 portant. Experiments were therefore conducted with some 

 local flour to determine whether the total per cent. P.^0.-, be 

 low, and if so whether it be the organic or inorganic which is 

 thus low, or both. 



Method. — 1. Total P-jO- determined in the flour weighed 

 both dry and in the natural state. 2. Alcohol-soluble 

 P2 O.- determined by extracting the flour with boiling alcohol ; 

 exaporating extract, taking up residue with ether, and de- 

 termining P2 O5 in the ether residue. It . is useless to 

 try to extract with etlier alone, for as early as 1891 it was 

 shown by Maxwell (15) that ether would extract only the free 

 lecithin, but would not take up any which was combined with 

 protein. 



The mean results oljtained were: — 



Total Alcohol Sol. P.Or.Hot ex- 



p Q p Q tractalde 



- '' '2 s v'ith alcohol 



Per cent, in the undried flour 0.1932 0.0278 0.1651 



Per cent, in the dried flour 0.2209 0.0322 0.1887 



The results show the total P./).-, to be low, and the alcohol 

 soluble moiety to be veiy small. Since bread is the mainstay 

 and principal foodstuft', particularly of the poorer classes, and 

 of vegetarians, the above fact is of physiological imi^ortance. 

 It is very generally recognised by agriculturists that to obtain 

 the best results possible the crops must be well numured by 

 some kind of phosphate manui'e. If this is not done, and the 

 crop has to depend entirely on the natural supply of phos- 

 phates, the entire yield is small, and individuar grains poor. 



