216 ANNUAL OF SCIENTIFIC DISCOVERY. 



this amount 37 grams are nitrogenous matter. This water is 

 treated with sulphate of aluminum, whereby all the phosphoric 

 acid, two-thirds of the nitrogenous matter, and rather mt)re than 

 one-iialf the potassium salts present are completely precipitated, 

 and perlectly clear, inodorous water is left, which may he run otf 

 into the rivers without injury to the purity of the water of the 

 same. — Chem. News. 



At llheims experiments have been tried on a large scale to de- 

 termine the value and applieal)ility of various processes for 

 tr(>ating the sewage of that city. The processes tried have 

 been: (1) treatment with sulphate of iron and lime; (2) 

 treatment with lignite and lime ; (3) treatment with line coal and 

 a small quantity of sulphate of iron and lime. The first two 

 pi'ocesses yield a manure, the third a fuel. The use of lignite is 

 said to prove completely successful. — Les Mondes. 



ACTION OF WATER ON LEAD. 



Dr. Frankland has made the observation that water which 

 acted on lead lost this power after passing through a filter of 

 animal charcoal. This he discovered to be owing to the fact that 

 a minute (juantit}' of phosphate of calcium from the charcoal 

 passed into the water. 



On comparing two natural waters, that of the River Kent, 

 which acts violently on lead, and that of the River Vyrnwy, which, 

 though very soft, has no action on lead, he found that the latter 

 water contained an appreciable amount of phosphate of calcium, 

 while none could be detected in the Kent water. 



Solubility of Carbonate of Calcium in Water saturated icith Car^ 

 bonic Acid. — Cossa linds that 1,000 parts of water saturated with 

 carbonic acid at the atmospheric pressure dissolve, of Carrara 

 rnarbli', at from 7.5° to 9.5°, 1.181 parts; of Luneburg chalk, at 

 from '20° to 22°, 0,835 parts; of precipitated carbonate of cal- 

 cium, at 18°, 0.950 parts; of Oolithic limestone, at 15°, 1.252 

 parts; of dolomite, at 15°, 0.573 parts. — Jour.f. Frak. Ch. 



SPECTRUM ANALYSIS. 



It is stated, in regard to the delicacy of the method of spectrum 

 analysis, that it is possible to detect 1-180, 000, 000th part of a 

 grain of sodium, 1-G, 000,000th part of a grain of lilliiura, and 

 l-l,O00,O00Lh part of a grain of strontium. 



The most important application which has yet been made of 

 spectrum analysis to manufacturing purposes is its use in the 

 m iking of steel by the Bessemer process. In this operation it is 

 all important that the blowing of air through the molten mass 

 should cease the instant the proper amount of carl)on has been 

 burncMJ out. '1 he jn-ccise moment at which to interrupt the bhist 

 is determined by examination of the ilame issuing from the con- 



