The sun. [volume] (New York [N.Y.]) 1833-1916, 1878-06-16

than ls found In the Cochltuato. Sulphatcs and
phosphatcs exert similar action, aud ithappens
that Croton water Is exceptionally rich In both
these classes Of salts. But 1t appears that phys
ical agoncios-as, for instance whore water Ia
delivered under grcatpressure-tond to impair
the influence of these substan 'cs, and to pro-
mote corrosion. So. too, when organic matter
is present Its action upon load is usually
prompt and positive. Thus, soon after lead
roofs were ln,r0dl ,od in Amsterdam. and the
metal was thus brought In contact with decay
ing wood, lead collie appeared throughout that
city in Il violent form. As rule, neither tho
Croton nor Coehtuatc water contains organic
matter. but the s,huylkil showed upon anily-
sis s-l00 of n grain to a gallon.
In presence Of all the facts collected by Mr..
Dayes. which include. besides those mentioned.
the effect of sharp bends and Of strains upon
the ripc. the frequent contact with that alloy of
lead and tin employed in soldering. and also
with rust from iron mains, we arc led to the
conclusion that lead pipe cannot bc used with
out some degree Of danger Of lead poison ny.
Probably nine-tenths Of the mischief wrought
by the metal on the human System escapes the
notice OF physicians. and there is no doubt that
certain waters can pass through lead pipes
without substantial contamination, even though
they take up enough to give lead
reaction under tho tests Of the laboratory.
Happily for those Of Us who are compelled to
use water supplied through such couduits.
chemistry Is not without resources for guard
Ing against their faint. Tho first and simplest
Of these is htration-chak. sand. clay. wood
charcoal. and. better still. animal charcoal nm
swerlng the purposc-while another excellent
preventive is TO limo the pipes with an insolublc
coating. We may add that methods Of deter
tffft.
within the ability Of ordinary plumbers no
chemical knowledge. but only careful manipu-
laton being required.
Load is an accumuativc" poison. but there
IS not perfect agreement among physicians rs
To- the gross amount requisite 10 reduce poi
sonous objects. DR.. Parkes. nm English author
ity. Prof Graham. and others. think that water
which contains e-twentirth Of n grain per
gallon must be regarded az unsafe. Small rs
this dose Is, some would fix the limit ~ security
at lower standard. DR.. Adams Of Waitham
Mass, reporting. n case Of poisoning in VII lch
only one-hun lredth Of grain per gallon was
found in the water. As above stated, however
there Is great variation in the susceptibility al
different persons to the effects Of lead. Thus n
case Is recorded 81 two members in family
made seriously III from the use Of water con.
tanning only. at times, n mere trace of III,
IlelNl-u ulNulltJ 50 luuAttslinai rs not 10 nave
tho least influence on the health OF others.
II ia clear that but FOR the Inconvenience At
tending the discoloraton Of water iron would
possess many Advantages over any other meta
rs q material for pipes. The publication OF
water by contact with iron is n fact we'll know
In chemistry Unuckily. most kinds OF poiRbl,
water contain either air or carbonlc acid gas IL
solution, which not only attacks metallic iron
hut also dssolves IL. Mr.. Bayles is Of Ia,
opinion that zinc should never be allowed {,
come IN contact with water which is To- bc use,
for drinking or cooking. There has been som,
diversity OF judgment on this point. but from
somo experiments lately made at Cleveland an,
at Columbia College It Is evident Lat zinc
oven when alone, is corrodcd and dissolve,
10y spring well. and river waters without cxccp
tion. Another danger. moreover. attendant on
tho use u zinc II the normal presence Of NOR,
Objectionable substances in competition Tn,
difficulty of obtaining this metal in commerce
free from arsenic Is plain enough from the fac
that such zinc sells Tor sixty cents pound
whereas ordinary spc.ter is quoted at seven o
eight cents. Here We may mention that pur,
tin s less acted up1n. either by wnter or saline
solutions. than ans other IL tho common n.etalr
ami rs the sH.t- o., TN are not poisonous then
detection Is Of no practical import 10 tn,
Number