SULPHUROUS ACID AND SULPHITES. 989 



SUMMARIES. 



In the summary for Nos. 1 to 6, inclusive, the quantity of sulphur 

 ingested in the food is seen to be slightly greater in the fore period 

 than in the preservative and after periods. The amount of sulphur 

 excreted in the feces is slightly greater (0.007 gram) in the preserva- 

 tive period than in the fore period and less (0.02 gram) in the after 

 period than in the fore period. From this it would appear that a 

 very small part of the preservative sulphur was excreted in the 

 feces, or, there was a less complete absorption from the alimentary 

 canal during the preservative period. a The data in the phosphoric 

 acid and nitrogen balances, in which there was a similar increase in 

 elimination of these elements in the feces during the preservative 

 period, seem to justify the latter conclusion. 



There is an average increase of 0.270 gram sulphur in the urine 

 during the preservative period, the quantity in the after period being 

 practically the same as in the fore period. This corresponds to a 

 percentage increase of 24.11, considering the first balance, that is the 

 sulphur in the food only, but even when the sulphur in the preservative 

 is considered (balance II) there is seen to be an increase of 6.75 per cent 

 over the amount excreted in the fore period. There is thus shown in 

 this general summary an increased excretion of sulphur during the 

 preservative period over that ingested as preservative. This is also 

 shown in the balances, there being a positive balance in the fore period 

 amounting to + 0.080 gram, while balance II, taking the sulphur of the 

 sodium sulphite into consideration, is positive, but amounts only to 

 0.008 gram. The first balance in the preservative period naturally is 

 negative, amounting to 0.234 gram, which is only 0.008 gram less than 

 the average quantity of preservative sulphur ingested. The balance 

 in the after period is positive, amounting to 0.057 gram. 



From these data, considered in connection with those for nitrogen 

 and phosphoric acid, it can be safely concluded that under the influ- 

 ence of the preservative there is a decrease in the assimilation of these 

 constituents and that the sulphur balance shows a decided increase 

 in katabolic activities, two conditions diametrically opposed to normal 

 metabolism. Considering, however, the special studies made of sul- 

 phur and sulphates in the urine (p. 839) , it is seen that the increase in 

 sulphur eliminated, over the amount ingested in the preservative 

 period, is due to neutral siliphur, and there is some doubt whether 

 sulphur in this form is due to katabolism. 



In the summary for Nos. 8 to 11, inclusive, the men who received 

 sulphurous acid gas, there is a fair agreement shown in the amount of 

 sulphur ingested in the food during the three periods, though there is 

 a slight deficiency in the preservative period. The quantity of 



See also discussion on p. 847, Table X. 



