Burlington weekly free press. [volume] (Burlington, Vt.) 1866-1928, 1869-11-05

flLrsRs-PURE WATER-The necessity for
pure water is probably fully appreciated by
most persons. BY pure water is not meant
water absputey pure. Perfectly pure wafer
IS only to be Iound in the laboratory oil the
chemist. Carbonic acid gas, common sAi''
Carbonate Of lime and some other matters are
ere present in almost all natural waters Wa
ter deprived If the gases. oxygen, nitrogen
! and carbonic acid although purer than water
containing them, would be vapid and tasteless
I like boiled water The most dangerous impu-
rites are those of organic origin. Clear spring
water and the water from deep wells, is usually
quite free from organic impurities; but all
water from slow running streams and muddy
ponss, well as rain water and water from
melted snow, contains much organic matter.
10 get rid Of this the water il filtered. Animal
charcoal forms the most efficient filter for re-
moving such impurities from water. Common
wood charcoal is very in.erior-nearly power
less. new form Of charcoal has been intro
ducei within few years, which is found to act
very energetically and to retain its powers for
long time. 1t is called by the inventor mcgTetic
carbide, and is produced by subiecting 10 heat
mixture of s.wdust and rel oxide Of iron.
The product is magnetic, and is ssi by good
authority to be superior to all other fliering
materisl, being equal 10 animal charcoal, with
/ the further advantage that it does not lose Its
/ power.
CoLoRISG OF SMALL METALLIC OBJEcTs-M
Puscher, German chemist, gives the following
receipts for the application Of sulphur 10 the
purpose referred TO- l. solution is made IN
the following manner Dissolve OF. OF the
hyposuphte of soda in a pint and half OF wa
ter, and then add solution Of o.. OF acetate OF
lead in the same quantity Of water. Articles to
be colored are placed in the mixture which is
then gradually heated to boiling point. The
effect Of this solution Is TO give iron the effect Of
blue steel zinc becomes bronze, and copper
or brass becomes, successfully, yel!ovish red,
scarlet, deep blue, light blue, blush white, and
finally. white with \ tnge Of rose. This 90
luton has no effect On lead or tin. By re- (
placing the acetate fiead il the solution by
sulphate Of copper, brass becomes first Of fine I
rosy tint, then green. aud, finally, Of = III \
descent brown color Zuic docs not color IN /
this solution; It throws down precipitate Of 4
brown sulphuret Of copper, but if boiled in
solution containing both lead and copper, It be
bcones covered with block adherent crust
which may be improved by = thin coating Of
wsI II the lead solution be thickened with
little gum trsg.csnth, and patterns be traced with
it On brass, which is afterwards heated to 2l2
degrees and then plunged in solution No. l,
good marked eject Is produced.
Portable lLLUNusAToRs.-M. Alvergniat,
French electrician, hss made Al improvement
frs, suggested to him when using the tubes
invented by Giesser, which are cylinders or
bulbs Of grass filled with rarifed gas that be-
comes luminous in the dark when current
Of electricity is passed through H. The i'm
proyement consists in filing glas. cylinder or
phial, Theoretically sealed, with substance
which becomes phosphore,cent by the action Of
FRACTIONAL or static electricity A tube Of this
kind may be some service to those on night
duty, for all that is requisite to produce
feeble and ephemeral light j; to rub the tube
lris1y with silk handkerchief