105 
MAGAZINE OF SCIENCE AND ART. 
ill health prevails in Sydney, from the use of water 
impregnated with lead. When this metal is introduced 
into the system in minute quantities it operates in- 
sidously, and the symptoms may be so diverse and 
olnseme that they are'never referred to their true origin. 
The lea’d is thus allowed to accumulate in the body 
until the constitution is permanently and even fatally 
affected. 
4. We have now to consider how the contamination 
of water bv lead may be prevented or remedied. It 
may seem at first sight that there can be no difficulty 
in accomplishing this, and that all we have got to do 
is to dispense with lead in forming pipes and cisterns, 
and to use some innocuous material; but unfortunately 
there are serious objections to most, it not to all other 
materials. If iron piping of small diameter be used, 
the water will probably get impregnated with iron rust, 
and in a few years the pipes will become choked with 
an ochery incrustation ; for the same qualities that 
enable a water to corrode lead, seem also to givn it the 
property ot’ corroding iron — the latter metal being at 
the same time more easily acted upon. Glazed iron 
piping (of which there is a specimen on the table) 
would probably be perfectly safe, hut it would be ex¬ 
pensive, and might be more troublesome to fit up. Tin 
piping would be too expensive ; and it would be dan¬ 
gerous if it happened to contain even a small propor¬ 
tion of lead. Glass piping has been manufactured for 
conveying water, but I am not aware ot any case where 
it has* had a fair trial. Pipes of earthenware are too 
difficult to beep tight at the junctions when there is any 
considerable pressure of water. As lead is decidedly 
the most convenient material to use, attempts have been 
made to render it safe, by a protective coating of some 
other substance. Dr. Chmtisomin discussing this mat¬ 
ter of lead impregnation, says, “an effectual remedy 
lias been lately introduced by a patent invention for 
covering lead pipes, both externally and internally, 
with a thin coating of tin.’* A firm in this city sent 
home lately for a sample of this protected lead piping, 
and they kindly allowed me to make some experiments 
on the specimen received. It turned out, however, that 
the lead was alloyed, not coated with tin; and it was 
more dangerous with water, than simple lead pipe. 1 
found that water kept in this lead pipe for 24 hours 
acquired no less than 75 degrees of lead. The reason 
of this may be understood from previous observations. 
The firm alluded to lmd another kind of pipe remitted 
to them as a sample; it was lead, with an internal coat¬ 
ing of gutta perelia, ^th ot an inch thick. In this case 
I fmind the lead was thoroughly pretected from corro¬ 
sion, but unfortunately the water acquired a peculiar 
taste and smell from the gutta perelia. I found that 
water, alter resting four days in this pipe, had dissolved 
three-fourths of a grain of organic matter per gallon in 
addition to what irihad previously contained ; but if the 
pipe was in constant use it would probably cease to con¬ 
taminate the water. „ ., .. 
If lead piping cannot be entirely dispensed with, it 
should be made as short as possible. I believe that 40 
or 50 feet of lead pipe will rarely do any harm, pro¬ 
vided that water that has rested in it for several hours 
he not used for drinking or cooking. I may mention 
that my laboratory is supplied by a pipe only 38 feet 
long, yet the water acquires 3 degrees or 4 degrees of 
lead by merely flowing through it If the water be al¬ 
lowed’to rest in the pipe the impregnation rapidly 
increases, and the first drawn in the morning contains 
usually between GO degrees and 70 degrees ol lead. 
This pipe, however, is one of the woist I have met with. 
A much greater length might he. used with lmpxjnity if 
the lead could be got pure, but a small proportion of tin 
(which is not unlikely to he present), would make it 
dangerous. These remarks a| ply of course only to 
Svdnoy water; in all other cases special trials must be 
made. Lead suction pipes for deep wells, and lead 
cisterns, should he avoided as much as possible, and I 
need hardly sav that lead cisterns for Sydney water 
should be entirely abolished, as this water will net bear 
long continued contact w ith load without being rendered 
poisonous. Si'ato cisterns may be substituted for lead, 
but, with a constant supply of water, cisterns may be 
dispensed with altogether. 
in cases where lead pipes or cisterns are presently in 
use, and where it would he inconvenient, or too expen¬ 
sive, to replace them with other material, it is in my 
power to prescribe a very simple remedy. It fortu¬ 
nately happens that mere filtration through sand will 
remove lead entirely from Sydney water. This method 
of separating lead was first proposed l>y Professor Clark 
of Aberdeen, and it was successfully applied by him to 
several cases of poisoned water in England ; but 1 had 
an impression th£tin all those cases the lead was not 
dissolved in the water, but was merely diffused in the 
form! of insoluble carbonate. Nov, 1 had tried the ex¬ 
periment of passing some Sydney water, containing GO 
or 70 degrees of lead, through a double filter of paper, 
and I had found that only a very little lead (some 10 
degrees) was removed; the inference bring that the 
most of the metal was dissolved, not diffused, in the 
water; and I was therefore not prepared to expect that 
filtration through sand would bo so successful as it 
turned out to be. To construct an extemporaneous 
sand filter I took a glass jar inches diameter, and 
open at both ends. Having closed one end with a piece 
of muslin, I filled the jar with sand to the depth of 
10 inches, and after washing the sand well with pure 
water, I poured upon it some water containing 75 de¬ 
grees of lead—the lead was completely removed, not 
the slightest trace remaining. I then kept the filter 
going/until 10 gallons of poisoned water had run 
through, but still not a particle of lead passed with the 
water, Bykeepingtlle surfart^of the waiter about H 
iach higher than the sand, 1 found this small filter de¬ 
livered at the rate of 14 pints per hour. Such an 
apparatus, on a larger scale, could be got up without 
difficulty in any house, and would free the water not 
only from lead, but from other accidental contami¬ 
nations. 
It is impossible to trace out, within the limits of a 
paper such as this, all the ramifications of the highly 
complex subject under discussion. I trust, however, 
that I have indicated, with sufficient clearness, a com¬ 
mon source of danger to health, and the means of re¬ 
moving that danger. I may give the sum of this paper 
in very few* words r many natural waters have the power 
of corroding and dissolving lead; they possess this 
power in different degrees; the source of this power is 
not rightly understood, and we cannot assert its presence 
without actual trial; if lead exists in water to 
the extent of 1 in 700,000 parts, the water becomes un¬ 
safe for domestic use; in larger proportions the lead is 
correspondingly more injurious; the water of Sydney 
is prone to take up a dangerous quantity of lead when 
left in contact with it; cisterns of lead should, there¬ 
fore, be discontinued, and lead pipes used as sparingly 
as possible; and lastly, water impregnated with lead 
may be restored to purity by filtration through sand. 
A lengthened and very interesting conversation^ on 
the subject of the above paper ensued, showing the im¬ 
portance the meeting attached to the rather startling 
revelations of the learned Professor, and the deep im¬ 
pression they had made, 
TRANSACTIONS OF THE AUSTRA¬ 
LIAN HORTICULTURAL AND 
AGRICULTURAL SOCIETY. 
NINTH MONTHLY MEETING. 
Held in the Royal Hotel, on Tuesday 
evening, October 6th, 1857. Mr. William 
McDonell in the chair. 
5[embers of Council present—Messrs. 
I Wm. McDonell, D. Mclnnes, P. L. C. 
