82 



PROCEEDINGS OF THE AMERICAN ACADEMY 



be in all had in some cases not been recognized. The only large suite 

 of analyses made by a single individual first fell under my eye in the 

 early part of June of 1848. In the following table are compared the 

 average total amounts of inorganic matters, and also the relative 

 amounts of the more prominent salts, in three wells, six springs, and 

 six rivers, as determined by Deville.* 



" The compounds of sulphuric and carbonic acids with oxide of lead 

 are eminently insoluble. The chlorides are less insoluble, and the 

 nitrates are highly soluble. t The contrast between the quantities of ni- 

 trates in well and river waters suggested the experiment with lead and 

 graduated solutions of saltpetre. | The results follow. 



Table XX. 



* Jinn, de Chem. et de Phys., 3« Serie, Tom. XXIII., pp. 33-47. 



i Sulphate of lead is soluble in not less than 15000 parts of water. Gmelin. — 

 Carbonate of lead requires 50551 parts of water. Fresenius, ^nn. der Chcvi. und 

 Phar., LIX., S. 117-128. — Chloride of lead requires 135 parts of pure water, 534 

 of water containing chloride of calcium, and 1636 of water containing hydrochloric 

 acid. BiscHOF. — Nitrate of lead dissolves in 1.989 parts of water at 63° Fahr. 

 Kaksten. — A solution of saltpetre containing 39 parts to 100 of water will still 

 dissolve 110 parts of nitrate of lead. — Gmelin. 



t O'Henry found nitrates in mineral spring-water in 1839. Journ. de Pharm., 

 Dec, 1838, pp. 634 - G37. — Liebig found nitrates in twelve wells in Giessen, 

 and none in the wells of the surrounding country, by experiments made in 1827. 

 " This fact has been noticed by Berzelius in Europe. I," says Dr. Dana, " have 



