78 PROCEEDINGS OF THE AMERICAN ACADEMY 



" June 19th. Worcester Railroad Depot, 500cc., exposed to the 

 lead 36 hours, reduced to 5cc., gave, of sulphide of lead, 0.00002gr * 

 = O.OOOlSgr. in a gallon. 



"The magnitude of this quantity, and the influence its known pres- 

 ence in a water should have, nnay be over-estimated. 



500 cubic centimetres contain 0.00002gr. 

 1000 " " " 0.00004gr. 



" Wiesbaden water contains of arsenious acid, in lOOOcc, 0.00015gr.,f 

 — a quantity more than ten times as great as the lead in Jamaica water, 

 and yet this water is renowned for its medicinal virtues. It may be 

 said, that the arsenic is in combination with oxide of iron. Chevallier 

 and Gobley have come to the conclusion, that its occurrence in springs 

 is not dependent upon the presence of iron.| It is found in water 

 whose character is determined by the presence of carbonic acid or 

 sulphates. This body occurs in solution in waters from nine mineral 

 springs in France. Its occurrence in Germany has been recognized, 

 among others, by Will.§ Tripier found it in Algiers. 



" The appearance of leaden pipes taken up after several years' 

 use, in New York, is what might have been expected. I have exam- 

 ined twelve pieces from as many different localities. Most of the 

 specimens that had been in use for only one and two years were cov- 

 ered with a bluish-gray coat, and some of them could scarcely be 

 distinguished from ordinary pipe for sale in the shops. A speci- 

 men in use five years is coated with a transparent, exceedingly thin, 

 reddish-brown film, apparently composed of organic matter, oxide of 

 lead, and oxide of iron. The crystalline laminae upon the inner sur- 

 face, characteristic of new pipe, are to be seen with the utmost distinct- 

 ness, and present, with the exception of the coating, no appearance 

 distinguishing it from new pipe. 



" Jamaica pipe, in use from fifteen to twenty years, is coated with a 

 thick, reddish coat, which, when dry, may be readily disengaged, and 

 in one specimen examined shows traces of slight corrosion beneath. 

 The corrosion from without was such as to have nearly eaten through 

 in some places. The lead of this pipe contained great proportions of 

 antimony where corrosion occurred, but no sulphide of lead, which, I 

 am informed, occurs in much lead pipe. 



* Precipitate ignited, redissolved, and re-precipitated, 

 t CoTiipt. Rend., Tom. XXIII., pp. 612-615,634,635. 

 t Journ. dc Ph. el dc Ck., 3 Ser., Tom. XIII., pp. 324 - 333. 

 § Aim. dcr Chem. und Pharm., LXI., pp. 192-204. 



