116 * Scientific Intelligence. 
have in my possession,” he says, “a section of supply pipe, removed from 
the aqueduct of a neighboring city, in a portion of which corrosive action 
had proceeded so far as to cause leakage. The part thus acted upon was 
confined to an acute angle, and there is evidence to show that the 
plumber, in placing it in position, bent it in the wrong direction, thus 
creating the necessity for another turn in the opposite. This pipe had 
doubtless been subjected to two violent turns, which seriously impaired 
the homogeneity of the metal. An examination of lead pipe removed 
from buildings will certainly show that’ where there has been any per- 
ceptible amount of decomposition, it has been confined to the angles and 
depressions in its course. ere are three causes or agencies which may 
perhaps be sufficient to produce these results:—1. The disturbance in 
could not be the case. 3. Corrosions may be produced in lead pipes by 
rtar. Where mortar is present, 
presence may be detected for months. The process of oxydation, which 
is retarded or prevented altcgether by the presence of neutral salts in 
water, could not be materially interfered with under the conditions con- 
of water passing through new pipes, with safety? In view of the manifest 
danger from local disturbances, the most sensible reply would be, never. 
A section of new lead pipe immersed in Cochituate water one hour, at & 
temperature of 65° F. gave a decided lead reaction with sulphydric acid. 
during two weeks. Varying the time of immersion in fresh portions of 
er from one to ten hours the lead indications continued, although at 
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