Diet Nutrition and Excretion of the Asiatic 

 Races in Singapore. 



Xo. 2. MANUAL WORKEKS. 

 By J. Argyll Campbell. 



This is the continuation of the work published in August, 

 1917, when the diet, nutrition and excretion of the local medical 

 students were dealt with (1) . In the present paper, manual 

 workers are under observation. 



As might be expected considerable difficulty has been ex- 

 perienced in obtaining material from labourers, but with the faithful 

 co-operation of several of the medical students and of others, a 

 number of analyses were possible. It is hoped that more will 

 be done in the future. 



Methods. 



Kidney Excretions. — The same methods were employed for the 

 estimations of nitrogen, ammonia, urea and chloride, as those used 

 in the previous research ( 1 ) . 



In addition, quantitative estimations of the phosphates and 

 uric acid were carried out. Phosphates were estimated by titration 

 with uranium nitrate in a solution of acetic acid, which precipitates 

 all the phosphate. The end reaction is either the brown colour 

 which is produced by an excess of uranium nitrate in the presence 

 of potassium ferroeyanide or the green colour formed by tincture of 

 cochineal with a surplus of uranium nitrate. 



The Hopkins- Worner method was used to estimate the amount 

 of uric acid present. 



Diet. — In some cases details, of the kinds and amounts of food 

 allowed to their workers, were obtained from employers. 



In other cases it was possible to weigh the food before each 

 meal. 



The compositions of the foods and their heat values have been 

 taken from standard books on the subject (2). 



Various Workers. 



Chinese Bakers. — Two Chinese bakers, employed by the father 

 of one of the students, supplied material for eight observations. 

 The average figures for the kidney excretions will be seen in Table 

 I. The amount was scanty, 807 c.c. This was due to perspiration 



Jour. Straits Branch E. A. Soc, Xo. 79. 



