New-York tribune., 1876-12-02

gran 10 I0 minus OF the mixture.
META1IC-COATED PoRCFLNIN-Tlanson Of Stock
holm mas patented process by which biscut-waro
can be coated with thick and adherent layer Of
metal-cOpper. gold, sver-that the articles have
every appearance Of massive metallic ones, and can,
like them. be engraved and chased. Prof. Schmidt
suggests that theprocess nearly reatedto the gal
VauO-piaStc.
PREPARATION OF PERFECTLY PURE BICARHONATE
or PoTAsH.-Pcsci recommends for the preparation
of perfectly pure bcarbonate of potash the passage
OF a current Of carbonic acid through a solution, in
so per cent alcohol Of caustic potash, purified 10y
alcoho and separating the biCarbOnate thus formed,
and washing 10 with alcohol ChlOrideS and ntIates
remain M solution.
SUGAB-WArER As 4 REMEDY FOR LIME IL THE
EYEs.-fhe highly injurious caustic effect of lime,
accidentally introduced into the eve, as frequently
occurs TO those engaged in building may be entirely
neutalized by the OF cold sug0r-water. owing to
the formation of a compound OF the lime and sugar,
which Is without any action upon the eyes
BLACK VARNIsH FOR METALLIC FANCY ARTICLES.
The following is recommended as rapid and
cheap method for vanishing fancy metallic articles,
especially Of east-ron: Heat tar quite hot 80 as TO
drive off all the water and volatile hydrocarbons,
nnd dip the heated, though not red-hOt iron
articles into it; allow them TO drain OIL over the
kettle, and then dry them perfectly IN drying oven
- 10 W 'N~
METHOD OF EXrRsCuNG CAFFEINE.-A simple
method of extracting caffeine from guarana, tea,
fce and other subs anCo for thcpUTp0sc OF deter
mining the quantity Of aibaloid contained therein,
consists in evapOrating the aqueous extract TO dry
ness along with some maguesla and powdered giaSS'
and repeatedly treating the residue Mlii clhtf pl
means of a peTcolatCr By this process almost pure
caffeine is dissolved out and can be crystailHed.
HEspERiDINE-Paterno and Briosi have prepared
hesperdine by Pfefers method from CiirHs dar0R-
fam, Eaopgm, mclicr, and other species. They
found il preferable to purify it by diss1ying it in
boiling acetic acid, out of which solution dark
Iosnous mass separated Immediately on cooling,
and out of the htrate trom IN alttr Nelal n'l5'
fine white cTvstals of hcSpcridne. They Iuyestl-
gated its feasibility, soubiity IN and reaction with
different reagents.
RESTORATION or THE POLISH TO FURNITURE,
IEATuER, &C.-FuTiture that has lost its polish,
floors and leather articles impaired in appearance
by use can be much improved by rubbing them well
with a wooden rag covered with very small guam
tty of paste made by stirring 81 parts of finely
shaved steaTin into ~ parts Of previously warmed
oil of turpentine, and allowing the mass to cool
The articles sh0ul9 be finally rubbed OIL very
thoroughly with a clean, dry coth.
Harmless GLAZE FOR EARTHENwARE.-A new
and harmless glaze has been proposed for common
earthenware intended 70 replace the poisonous lead
CaLc Illal Is u>uall tiil4"NtN' NilN vi t' A.'ii'
recommended for this purpose consists Of 100 parts
o. icate of soda - parts of powdered quartz, aud
. PARTS OF Mcud0u chalk, and second Is tue same,
huf with the addition of 10 parts of boray which
renders the glaze fusIble and more brilliant.
Any desired color eau be given to tins glaze.
A NEW DYE-STUFF FROM ARTIFICIAL ALlZARINE.
-R0scuschl has obtained, by action of nitrous acid
o. dry, artificial aIzaTine and subsequent treatment
aud isolation by chorofom, yellow scales, Of metal
.-g, H.. .lr-ov %t n1t
rorlant, and a rcddl>h-yiolet with iron moriant.
The colors are not only fast in boiling soap solution,
lut even become lYelitr 1t is best to employ dis
tiled water or water with acetate Of lime added To-
il. Ihe new color seems 70 have inc lollhdid Ol
utro-alzarine.
INSULATING Co,IPoUND FOR TELEGRAPH War
Anew insulating compound, SAID to be well adapted
for covering telegraph wires consists simply of the
refuse Of ozokerit fossil found in Russia, mixed
with india rubber and gutta percha. It's impos-
sible to break OF crack this by fair treatment, ana
81 is unaffected by any temperature below that
which approaches It's melting point Nhhe us IN
Conducting capacity D. less Ii can be FURNISHED al
about hall the cost OF gutta peIcha
REVOLVING SHow-CAsE.-A revolving showcase,
with l6 radiating vertical leaves, upon which aTti-
clcs to be exhibited can readily be fastened with
pins, &C.. is being introduced into schools in Ger
many, as well as into the shops. Among It's advan-
taces are enumerated the great economy of space
the possibility OF displaying each article under the
most favorable illumination, and the arrangement
Cf drawings, DC, IN any desired order, Whe such
case placed IN a window could be made To display
during the day Tar greater NaIlety OF pictures
photographs, &c, than case made upon the isudi
plan.
PREPARATION OF VERY ACTIVE PLATINUM-BLACK.-
Zdrawbowitsch has found that platinlc chloride Is
reduced by gycerne by the aid of heat but that the
platiuum-black formed is but fcebly active. But If
the chloride solution is gradually added TO boiling
mixture of 10 volumes of glycerine with 10 of
caustic potash solution, Of a specific gravity los
the metal Is instantly precpiated as a very encr-
getic platinum black. SOmestmes, especially II
more potash is employed, metallic mirror is formed
BOttger adds that a similar result may be obtained
by heating platniC chloride solution, 10 winch some
grape sugar and caustc soda nave Deeh ADDED
TANNING WITH THE AID OF ELECrucITY.-In a
communication to a French journal 1t is stated that
if through reservoir filed with solution Of taunn
an electrical current passed by means Of plates OF
gas-carbon placed in the bottom and connected
through wires covered With gutta-percha with the
positive pole OF a magueto-clectTic machine, and
though a plate Of zinc covering the upper surface
of the solution with the negative pole, the heaviest
leather Instead Of requiring II TO - months, viii
be tanned in 30 TO 80 days, the hides nearest the
positive pole being invariably finished first.
PoIsOyoUs CHARACTER or TIE BLOOD AFTER
DFATg.-SiCnoI a French veterinary surgeon
claims to have established beyond a doubt, By
1nerous experiments that while the blood III the
perfcial veins is harmless that in those that lie
deeper is so highly poisonous IG hours after death,
Of every perfectly healthy animal, whether siaugh-
tered or sutocated thai u drops Oi it introduced