August 24, 1906.] 



SCIENCE, 



243 



of Mr. Matthews, at a depth of 1,270 feet. 

 The bed was 70 feet in thickness. The first 

 shaft for mining the rock salt was finished 

 in 1885, It is situated near Piffard, Liv- 

 ingston County, and is 1,018 feet deep. It 

 is called the Retsof shaft. The Greigs- 

 ville shaft is about one mile south of the 

 former. The third shaft is two miles south 

 of LeRoy and has a depth of 825 feet, and 

 the fourth shaft was sunk at Livonia, Liv- 

 ingston County, to a depth of 1,430 feet. 

 But one mine, the 'Retsof,' is at present 

 operated. 



All the salt wells of the state Mdthout 

 exception, as well as these four salt shafts, 

 obtain their brine or salt from one and the 

 same rock-salt deposit, situated in the 

 ' Upper Silurian. ' It extends f yom Morris- 

 ville, Madison County, to Lake Erie, and 

 from LeRoy to Watkins. The salt stratum 

 is over 100 feet in thickness, depending 

 entirely upon the configuration of the 

 ground below the Silurian sea at the time 

 of its formation. The rock salt occurs in 

 one vein, two, three, four, five, six or even 

 seven veins of various thickness and depth 

 from the surface of the ground. The dip 

 of the rock is southwest, about 41 to 46 feet. 



The Solvay Process Company, after three 

 attempts, finally obtained rock salt almost 

 directly under the Tully Hills, which are 

 300 feet above, and has at present 51 wells, 

 30 on the east side, and 21 on the west side, 

 of the Onondaga Valley, which at the pres- 

 ent time supplies them with the brine re- 

 quired for the manufacture of soda ash, 

 caustic soda, baking soda, etc. 



Sources of Some Common Impurities in 

 C. P. Chemicals: James W, Schade. 

 The object of this paper is to present the 

 sources of impurities in chemical reagents 

 and to show that there are limits to the 

 purity obtainable by manufacturers. The 

 sources of impurities are: (1) the contain- 

 ers in which chemicals are shipped; (2) 



tanks, stills, condensers, and so on, in which 

 chemicals are made; (3) reagents used to 

 precipitate certain impurities or compounds 

 formed by these reactions; (4) minerals 

 from which the chemicals are made and 

 materials used in manufacture. The 

 danger of contamination by impurities of 

 the first two classes may be minimized by 

 careful selection of material for containers 

 and apparatus. The presence of both ba- 

 rium and sulphate in a sample of sodium 

 chloride and of cakium in ammonium 

 oxalate are examples of impurities of the 

 third class. Impurities of the fourth class 

 are illustrated by the persistence of calcium 

 in barium compounds and the constant as- 

 sociation of nickel and cobalt in their puri- 

 fied salts. For ordinary work, however, 

 reagents that will give accurate results can 

 be manufactured at a reasonable cost. 



On the Determination of Carbon Bisul- 

 phide and Total Sulphur in Commercial 

 Benzol: Edward S, Johnson. 

 (1) The Determination of Carbon Di- 

 sidphide.— The principle underlying the 

 method seemingly most widely applied is 

 that of the transformation of carbon di- 

 sulphide by means of alcoholic potash^ into 

 potassium xanthate, utilizing this substance 

 as a medium for separation. For deter- 

 mination the potassium compound is best 

 converted into cuprous xanthate and the 

 latter into CuO. Much uncertainty exists 

 apparently as to the exact composition of 

 the so-called cuprous xanthate. If consti- 

 tuted as represented by the formula 

 (CS.0C2H5S)2Cu2, the ratio of CuO pro- 

 duced to CS2 entering into the formation 

 of the xanthate should be 1.0:0.9563, 

 Macagno^ found 1.0:1.931, a little more 

 than twice the theoretical. Others have 

 obtained similar results. As evidently 

 cuprous xanthate is not the compound un- 

 der consideration, an investigation seemed 



^ Nickels, Chem. News, 43, 148. 



^Chem. News, 43, 138. 



