CHEMICAL SCIENCE. 205 



ing the water with which they had been furnished. The water of one 

 was obtained from a marshy place where the ague was prevalent ; that 

 of the other from an elevated position where the ague did not prevail. 

 Soon after sailing, the troops on board of the vessel supplied with water 

 from the marsh spring were seized with remittent fever, while not a 

 case occurred on board of the other vessel. Dr. A. Smee, who was 

 present, stated as his opinion that as a rule all animal excreta in water 

 should be considered poisonous to animals of the same class, and all or- 

 ganic matter of a decomposable character in water was highly preju- 

 dicial to health. 



DEODORIZATION OF SEWAGE. 



A late number of the London Journal of Gas-Lighting and Sanitary 

 Improvement contains a report of Dr. Letheby, on the deodorization of 

 sewage at Northampton, England, where there is an establishment for 

 the purpose. About 100,000 gallons of drainings from the sewers are 

 received at the works daily. Lime and the chloride of iron are used 

 for defecation ; ten bushels of the former and sixty pounds of the latter 

 are used for 1 00,000 gallons of sewage. The two substances are mixed 

 with water in separate tanks, and the solutions flow over in graduated 

 quantities, into a common discharge pipe, whence they pass into the sew- 

 age as it flows from the outfall of the town into the subsiding tanks. Here 

 the solid matter precipitates, and the comparatively clear water runs 

 away by an overflow at the opposite end of the tank, into the outfall- 

 ditch. After working continuously in this manner for about a fort- 

 night or three weeks, the solid matter, in a slushy condition, is drawn 

 up from the bottom of the tanks, and run into prepared pits, where it 

 is mixed with about its own bulk of ashes. This gives consistence to 

 the material, and converts it into a solid compost, which is sold for 

 manure. Respecting this mode of deodorizing the sewage, Dr. Letheby 

 says, 



" The chloride of iron should be dissolved in water, and allowed to 

 run by a graduated stream into the sewage before it reaches the lime. 

 A contrivance should also be used for effecting a perfect mixture of 

 the iron solution with the sewage. This having been accomplished, the 

 sewage should then receive its dose of lime-liquor, and be again well 

 agitated, so as to be thoroughly mixed. In this manner, a heavy, clot- 

 ty precipitate will be produced, which will rapidly fall in the subsiding 

 tanks, and leave the supernatant liquor clear, and perfectly inoffensive. 

 The proportion of chloride of iron and lime should be about 4 or 5 grains 

 of the former, and 14 or 15 of the latter to a gallon of sewage. The 

 total for a day's working with 100,000 gallons of sewage would be about 

 64 pounds of the former, and about 200 pounds of the latter. The 

 quantities should be so regulated that the supernatant liquor at the 

 outfall should be clear, colorless, and but faintly alkaline. With this 

 modification of the process, I am of opinion that the sewage works may 

 be conducted and managed so as not to be at all offensive or injurious 

 to those who reside in the neighborhood." 



SUGAR AS FOOD. 



Mr. Bridges Adams, the English physiologist, in a recent paper on 

 the " Uses of sugar in assisting assimilation of food," says, " I know 

 18 



