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a one-inch lead pipe, and although this pipe had been in 
use for 21 years, and the water which passed through 
it contained certain proportions of sulphate and carbonate 
of lime, yet the pipe had not become coated as M. Belgrand 
says is the case with the lead pipe in Paris, and as is 
generally supposed to be the case, but was, according to the 
description of the owner of the house, as free from inside 
coating when taken out as it was when put in. 
I was asked to suggest a substitute for the lead pipe, and 
advised the use of tin-lined lead pipe where the coating was 
about l-16th to l-20th of an inch thick, because some 
samples which I had obtained and examined several years 
before did not in the slightest degree contaminate water 
when kept in the pipe for many days. My suggestions 
were carried out, and a sample of the water which had 
passed through this tin-lined pipe sent to me for examination. 
I found it to be contaminated with lead to a considerable 
extent, and on examining some of the tin lining I found it 
to contain a large proportion of lead. I sent to another 
manufacturer of this tin-lined pipe for a sample. This he 
sent me, and again I found that the tin lining contained a 
large proportion of lead, and quickly contaminated water left 
in contact with it. This I communicated to the manufac- 
turer, who informed me that he could not understand how 
the tin lining had become contaminated, unless it was by 
its being poured down the side of a strip of lead into the 
hole left in the solidified lead in the cylinder previous to 
forcing it through the dies by hydraulic pressure. As I 
understand this pipe is produced by pouring melted lead 
into a cylinder, through the top of which an iron shape is 
introduced to make a cavity in the lead of sufficient size to 
hold the necessary quantity of tin; the lead is then allowed 
to set; when this occurs the iron shape is withdrawn and 
molten tin poured in to fill the space which the iron shape 
previously occupied ; a “ die” composed of an iron tube with 
