64 Mr Dal ton 07i the Comparative Quantities of' Food 



total quantity of urine for the fourteen days was 680 ounces ; 

 and the total quantity of faeces 68 ounces. 



The daily average was, urine 48J oz., faeces 5 oz., a greater 

 disproportion than was anticipated, being nearly in the ratio of 

 ten to one ; they amount together to 53^ oz. or 3^ lb. nearly ; 

 hut the quantity of food taken daily was 91 ounces ; there re- 

 mains a balance of 37^ ounces to be accounted for, which must 

 have been spent by the insensible perspiration from the skin, 

 and that from the lungs conjointly, on the supposition that the 

 weight of the body remained stationary. 



I have already observed that the daily evacuations were not 

 so nearly uniform as was the quantity of food. The urinary se- 

 cretion was greatest when tea was substituted for milk, and on 

 one day was 15 ounces above par. On another occasion, find- 

 ing a greater defalcation than I had before observed, I could 

 discover no cause for it, unless a tea-spoonful or two of vinegar 

 taken at dinner could account for it. To be satisfied of it, I 

 took, some days after, an ounce of vinegar in four equal portions 

 during one day; and the effect was a greater diminution of 

 vu'ine on that day than on any other during the two weeks, the 

 quantity being 15 ounces below the average, and 4 ounces less 

 than the former day, when vinegar had been taken. There did 

 not appear to be any increased effect in any other secretions, as 

 a compensation for this diminution. 



In order to try the effects of different seasons, I resumed these 

 investigations in the month of June the same year, and continued 

 them for one week successively. The results were what might 

 have been anticipated nearly. A less consumption of solids, and 

 a greater consumption of fluids, were observed. The evacua- 

 tions were somewhat diminished, and the insensible perspiration 

 was increased. 



The following were the results : — 



Solids consumed in aevm days. Fluids consumed in seven dayp. 



236 ounces. 391 ounces. 



Per day, 34 ... 56 = 90 Total. 



being 4 ounces per day less in solids, and 3 ounces in fluids, than 

 in the former trial. 



