The Stourbridge Observer, Cradley Heath, Halesowen & District Chronicle.
Stourbridge, West Midlands, England, 1874-11-14 00:00:00

LECTURE ON "WATER" AT THE UNION

HALL.

A lecture on the above subject was delivered at
11 the Union Hall, on Monday evening last (under
I the auspices of the Church of England Associa-
tion), by the Rev. W. J. J. Welch, MA., Head-
master of the Gramma' School. The room was
well filled by a highly respectable audience.
The Lecturer opened his subject by remarking
that they would perhaps remember he had endea-
voured to explain to them the properties of "the
air we breathe," and he thought the subject of the
present lecture "the water we drink," would form
a fitting sequel to that. If it was true that there
were thousands of persons whose healths were iin-
paired by constantly breathing impure air, it was
no less true that thousands of liveswere shortened
by the constant use of impure water. lie
then read a few extracts from the Times of July
the Ist, 1869, which stated that in the two pre-
vious years no less than 122,00 U persons had
perished from drinking impure water, In Eng-
land, Scotland and Wales, more than one•third of

the illness was caused by preventible diseases. I
Impure air and impure water were killing their I
thousands. Chlorine, as it was termed, was most
fatal when it was combined with impure water.
People were warned against keeping water in the
house when infectious diseases were present, be-
cause it would absorb the vitiated air. Another
writer said that he found that disease
in some places prevailed in exactly the same
proportion as the people procured the water from
the same source. The lecturer then went on to say
that he had an immense mass of matter to quote
frow, shoufing the deleterious effects of impure
water, but as a lecture with experiments occupied
a considerable time, he would confine himself to
what he had already read. Until the year 1781 water
was considered to be an element, that was to say,
composed of only one kind of matter. It was then
that Cavendish found that it was composed of two
kinds of mattes—oxygen and hydrogen. He pro-
posed CO show them some of the properties first of
hydrogen gas, and then of oxygen gas. Ile would
do this by the aid of a simple machine. He had a
Woulff's bottle containing granulated zinc, and he
would add sulphuric acid and as the zinc acted upon
the sulphuric acid the gas evolved would be hydro-
gen. It was transparent and inodorous. He then
ignited the hydrogen just formed, and directed
their attention to the fact that the flame emitted
very little light but was of considerable heat.
They would learn from that, that it was combus-
tible. Hydrogen gas was, therefore, transparent
colourless, inoslorous, and it was the lightest body
known. He next proceeded to demonstrate the
lightness of hydrogen gas, by making soap bubbles
with it, which were afterwards exploded by apply-
ing flame to them. Oxygen was likewise tasteless
and inodorous, but it differed from hydrogen in the
fact that although it was a powerful supporter of
combustion it was incombustible. That meant
that combustibles would burn in it with greater
brilliancy than in atmospheric air. He then pro-
duced a glass jar filled with oxygen gas. Many
people thought that if a lighted torch was thrust
into a gasometer an explosion would immediately
result; but this would not be so. The torch would
forthwith be extinguished. That was caused by
the absence of oxygen. Phosphorus did not burn
with a very brilliant light in atmospheric air, but
in oxygen it burnt very brilliantly. He next made
use of the voltaic current and the eudiometer to
prove that water was composed of hydrogen and
oxygen. Ile did this by synthesis and analysis.
To produce the required amount of electricity for
this experiment the lecturer made use ot the elec.
troporus, which, having been previously covered
with resin, he briskly rubbed it with a cat's skin,
until the necessary amount of electricity was ob-
tained. Water consisted of two gases which were
united together by chemical affinity. To analyse
them the two gases might be mixed together in
any quantity, but they must be heated whilst in
their mixed condition. He showed them how to
separate the gases by means of the voltaic cur-
rent. The hydrogen gas was given off in small
bubbles at one end and oxygen at the other; the
larger volume being hydrogen and the smaller
oxygen; the proportion of hydrogen to oxygen
being as two to one. The mixed gases having
been placed in the tube, he exploded them, and
there remained in the tube but a few drops of
water. The lecturer said they had now formed
water by synthesis. They had turned it into the
two gases of which it was composed; they had
brought them together and exploded them, and a
little drop of water had resulted. They would
now separate the 'oases and tear the molecules
apart. They would find that the volume of gas
in the one tube would be double the volume of that
in the other. He next spoke of the colour of water
which, he said, was, wherever present in large
quantities of a bluish tinge. In lakes or rivers it
would defame various colours according to the
colour of the bottom. He then proceeded to des-
cribe the properties of water, the principal com-
ponent parts of which were calcium carbonate
(chalk), sodium chloride (common salt), calcium
sulphate, magnesium sulphate, &c. The freshness
of water was due to carbonic acid. It was in
density 730 times that of atmospheric air. Those
were all the properties of which he should make
mention that evening. He described hydrostatic
principles, which he illustrated by a small working
model of Bramah's Hydrostatic Press; and stated
his conviction that as hydrostatic principles were
better known water would be more commonly used
as a motive power. Its greatest principles were
its power of finding its own level, and that its
particles had no friction; and it was these two
qualities which rendered it so valuable as a motive
power. His next subject was the fusion of metals
which he illustrated by means of the oxhydrogen
blow-pipe, by the aid of which he melted a piece
of watch-spring in a few seconds; and he pointed
out the singular fact that oxygen and hydrogen,
which, when in combination as water, were the best
means we had for extinguishing fire, produced in
the form of gas the greatest heat of any substance
known. He next reminded them that the flame
, of hydrogen gave Out little light, but he would
show them that, combined with oxygen, it would
, produce the most brilliant light they could con-
ceive. The lecturer then ignited a tiny jet of by.
drogen, and caused to mingle with it a thin current
of oxygen, and made the flame to play upon a
small cone of lime. The light produced was daz-
xlingly brilliant. The leeturer stated that this
was the oxhydrogen, light which was used for
magic lanterns. He theu referred to the impuri-
ties contained in water, and said it was a common
: falhicy:to suppose that rain water was perfectly
pure. But this was not the case; as rain absorbed
all the impurities of the atmosphere. He then
, proceeded to test some water which had been sent
to Mr, Bland's laboratory for the purpose of being
analysed. The lecturer now tested them by what
was known as " Nessler's Ti at," and the result was
that all were shown to contain a large amount of
organic matter. He next exhibited the' Ashantee
filter," which he had so designated because it was
used during the recent campaign by the soldiersof
the British army. The lecture was a very interest-
ing one, and was illustrated by numerous chemical
experiments, in the making of which the lecturer
was ably assisted by Mr. T. Bland, jun.
Mr. Collis proposed a vote of thanks to the lec-
turer, and said fitourbridge was to be congratula-
ted on having a gentleman of such scientific attain-
ments within its precincts, who was willing to im-
part his knowledge to those who chose to hear it.
' The proposition was seconded and carried with
acclamations, and the meeting terminated.