140 FIRESIDE SCIENCE. 



ety need be felt. It is perhaps impracticable to have 

 chemical analysis of waters made upon so extensive 

 a scale, but it is -the only way in which there can 

 be perfect exemption from cases of lead poisoning 

 in cities. In a majority of wells, lead conducting 

 pipes can be used with safety ; but since without 

 analysis it is impossible for housekeepers to know 

 when the conditions are unfavorable, it will be better 

 to employ some other kind of pipe. It may be said 

 here that we have used water in our own dwelling 

 for twenty years which passes through leaden ser- 

 vice-pipes from the iron mains of the city of Haver- 

 hill aqueduct. Not a trace of lead has been found 

 in the water since the first month after its introduc- 

 tion. If we did not know that we are free from 

 agencies causing local decomposition, we should re- 

 move the pipes at once. 



TIN-LINED LEAD PIPES. 



To obviate the danger incident to lead pipes, an 

 inventor in New York conceived the idea of lining 

 the interior of such with tin. These pipes are 

 called " tin-lined lead pipes." They are con- 

 structed of a thick outside pipe of lead, while 

 another thin one, of tin, is drawn through the inte- 

 rior and rests in contact with it, forming a lining. 

 This idea is such as would quite naturally suggest 

 itself to any one ; and ingenious mechanics or in- 



