New-York tribune., 1871-01-19


A New DIsINFECTANT.-The hydrated chlo-
ride of aluminium, long known to chemists has lately
teen extensively used disintecting agent Its read
lily made by dissolving alumins in hydrochlorc acid
solution evaporating leaves crystals of what was
formerly called the sesquchoride of aluminium in com
bnatiOn with three molecules Of water The atomic
weight Of aluminium having been doubled by agreement
Of advanced chemists the sesquchOrde becomes the
frichoride OF aluminium. The hydrated compound has
all the virtues of the chloride Of zinc without any OF s
dangerous qualities arrests decomposition and de-
stroys disease germs, and still not injurious or danger
eases Of sore throat, diphtheria hooping-cough or
scarlet fever 1t has sweetish astrlngent or snnous
taste virtues derived from the chlorine con-
tained it, being highly charged with ina, eie
ment than common salt IL has been successfully used
sntseptic and in the preservation OF food
New PROCESS OF CASTING METALs.-1he
London Quarterly journal Of Science that eonsd-
cradle number OF gentlemen lately met at the lanca-
SHIRE Engineering and Compression Casting WORKS OF o'
Heens Junction witness the new process OF casting
In and ron and embossed work oil the most
rsborate description. The process which was then or
The first time exhibited In England, is an American In
yenton and it's utility was shown to consist IN tbs m
metal OF any required pattern or shape whether nal a.
aoorplate or round a. vsse can be Iepr9dncen oy
TIE sharpness of the original chasing mIid are nsos s
sse mods sSes from five to ten minutes They
stand twenty four hours exposed 10 dry ar after
These clay mOlds. which the metal is afterwards
poured arc all uiens and purposes, encaustic tiles
he Inods placed i'll a box and the air is extracted
from them so as 10 form q vacuum, after which the
%Tes Hea % cssns csn be completed When the casting
taken out the design however intricate II found 10 be
perfectly represented with the exception of removing
Slight surface clay from it, which can he done in half
m hour and the article is then ready 10 lie sent TO the
In this way an enormous amount Of cost and labor
ornamental articles In metal Is saved
ARTIFICIAL PREPARATION OF lNDlGo.-Ihe
1ndssa Gazette of Cbemnitz, saxony, that in the
beginning OF 1870 Baeyer and Emmerlng OF Berlin,
found that indigo might prepared from isatin which
latter may be produced from cnnamonie acid. This
mode of preparation, however, was attended with a
serious drawback account of the difficulty Of obtain
ing the acid. Quite recently, however En-
mernc Euger discovered that the same result may
be accomplished by means Of benzoic acid which is
quite easily obtained from the urine OF horses. IL s
pccted that by improving this method the importation
Of indigo from Oriental countries will be cou sideraby
diminished mixture of benzOate of lime with acetate
of lime If subjected To distillston. yields compound
which he regarded the alcohol Of benzoic acid in
which the hydrogen OF the water has been replaced by
the radical methyL f this body Is treated with strong
nitric acid product containing nitrogen is obtained ia
which atom Of hydrogen replaced 10y one atom OF
reaction which is here omitted but il will readily nm
derstood when state that II only differs from the
two atoms of hydrogen and two of oxygen Now, by
simply adding hydrogen, which Is accomplished by heat
ting the compound with mi Nture OF soda, lime and zinc
dust Is formed and indigo obtained although in
very small quantity We may sere remark that Bseyer
cipal pigment from maddcr alizsrin which il now man
ufactured large scale In Germany.
IMrAcT.-In Foggendo,.gs Armaien Mr.. L. Hagenbach
applies the mechanical theory Of heat 10 for
some Of the results OF the experiments recently made
Base the view OF using targets Of iron instead OF
wood in practice with fire Strong plates Of iron
were fred at from short distance of PAGES Conf
cal bullets by their impact against the iron plate pro
nced scarcely indenaton, and fell down
the target; at time the lead projectie was
melted 90 avery considerable extent. The cond be
cognzed the fact that around the point where the nall
had struck the plate spateied with lead in the form
of a white star; that, moreover the melted lead was
found in the vicinity aud that OF the original bullet, which
weighed 30 gamines, oIly The Comparatively small por
tion Of - grammes remained by the authors cacula,
equivalent OF the heat 0i9 thermal uuit lie then pro
e deserbed The entire oectile 40 gramncs
had raised to the temperature OF the melting point
Inming ioco C. a. the initial Temperature of the ball
which somewhat warmed by the heat OF combustion
and by friction the melting point Of lead being 1885, c.
its specific heat OOi and its latent heat OF fusion 53 he
nnds necessary for heating o thermal npi ana Tor
only 05 than the estimated mechanical equivalent
Thus the mechanical theory ~ heat sufficiently accounts
for the operation Almost AL the impetus OF the motion
of the body transformed into heata result which was
very slightly deformed the proieetie rebounded but
little BY far the greater portonof the heat was used In
stood Tor the short time within which the entire process
Was elected could gFe rise TO but little loss by conduc
SIEhAN's PYRoMETER-T This instrument was
The subject Of considerable discussion the last meeting
ote BIsh Association for the Advancement OF Science
It's entrey unlike those promoters which indicate
high degrees Of temperature by means Of difference
in diaton OF two solids exposed TO the same tempera
ture. Such promoters have found nntrusworthy
principally from two first the rate OF expansion
exposure 10 regularly increasing heat is not uniform;
second certain metals and solids do not resume
their original length after Being heated and cooled The
indications obtained from promoters of.this class ex-
posed very high temperature have never been trst
.ftrflN flara laal lsGf such
actual heat used in many chemical experiments thai mo
definite conclusions could DE arrived al as W =,
nhange MI. sieDaD's pyrometer has taken advantage
Oi the Iaet mat electric force slowly rOn0h
N platinum or an iron wire proportion a. il il exposed
.0mgher degrees of heat Platinum, requires
Nghef neat u reduce than other metal sDce A
nnlN Yields before the name Of The hon