136 FIRESIDE SCIENCE. 



the cheapest and most convenient material of which 

 to construct them. It is soft, ductile, easily and 

 readily put in position, and seldom gives trouble by 

 leakage. It is a pity that a metal so well adapted 

 to our wants should be liable to be dissolved by the 

 water brought in contact with it, and that the metal 

 and its salts should so disturb the vital functions as 

 to engender disease and destroy life. And yet, we 

 cannot help remarking, how slight is the danger 

 from the use of lead water-pipes. Millions of 

 pounds of it lie buried in the earth, and through it 

 water is flowing to thousands of families, and yet 

 comparatively a small number suffer from its influ- 

 ence. A large proportion of the waters of this 

 country, that are suited to culinary purposes, will 

 pass through lead pipes under ordinary conditions, 

 and remain uncon laminated. During the past 

 quarter of a century, we have studied diligently this 

 matter of the action of different waters upon lead, 

 we have made hundreds of analyses, and have found 

 but few from ponds, lakes, and open reservoirs that 

 do not contain elements \vhich exert a protective 

 influence upon the surface of the metal. The first 

 chemical action of water upon lead is usually that 

 of oxidation. The oxygen, which enters into com- 

 bination with the metal, comes from the air always 

 present in water, or possibly it may come from the 

 water itself through chemical decomposition, the re- 



