The sun. [volume] (New York [N.Y.]) 1833-1916, 1892-07-17
SorKs ON SCIENCE AVID IyDUsrnE

A new artificial stone is proposed by a Cor.
man inventor. the material consulting simply
OF ten parts OF siliclc acid. powdered and freed
from impurities, and mixed with ninety parts
OF water and 100 Of anicklime. all by weight
aud Of this product 100 parts IRE mixed with
100 parts OF sand ana Ave parts OF mn rnesia or
fuorspar, the mass being thcn moulded ns de-
sired. The articles are allowed to dry for
Ing subjected to steam pressure under
ten, atmospheres. pressure for. some forty.
eight to ,.,, seyenty-two hSnrs they. are
pheres for siS to twelve hours, then to. be dried
stitute for the sand. marble. magnesix, mag.
nesium limestone, DC; answer tho purpose
said to resemble marble sandstone. granits.
kc.. very closely besides being tlreproot and re-
sisting the action OF the weather.
Among the recent novelties in camera pro-
duction are the prints on plain sailed paper.
toned with platinum, the method OF procedure
being to take the well-known plain sailed pa
per In ordinary Photographic use and silver 10
on n bath OF sixty grains nitrate OF silver to
the ounce Of water. or 1t may be put on with .
the paper becoming dry. " IS printed. without
mence TO bronze: and before toning. the
prints arc to DO thoroughly washed, to remove
acid nnt red and t then nSSS from The
acid bath to clear water and from the latter to
d s9 Of IN th9
,!rors Of nitric, acid and thirty ounces q
water When, the prints reach the desired
slightly alkaline with carSenate Of soda for
few minutes. and then put into a hypo bath
Ing. after which n thorough washing in water
eliminates the hypo; the product is q beautl:
tainod when negatives having considerable
contrast are employed.
Some new alloys for the manufacture OIL er.
Ing and cutting tools are announced In :As
Sheffield. England, papers. and which are SEA
to POSSESS u hardness equal to that Of tenn.
pered steel. with the further advantage Of not
Gsinx Their when heated s6n Iy friction
charcoal and calclned borax. the tunr:
s anu I'll" alloy e ptcdSsed Is Then 'ee
melted in clay crucibles together with the bnr
Extraordinarily sdded Ths metal Is hIs o tims
covered with stick charcoal only and the al.
are Jndes four
out tools: and the like. tho alloy con sists Of
eombination OF pig iron. Swedish bar iron.
lerro-munganese. chromium, tungsten. alumni.
num-. nickel. and copper
Hot blast furnaces are now being con instructed
Ill bu'H rs W use tIle nehI u6FlNeN
from tho furnace for heating the air blown
into it TO smclt the contents Tho mode Of
carrying out this plan is by letting Into the
brickwork. on all sides Of the furnace. several
chambers immed ntely over the tuyere pipes
sss Of e ssss a inner
air masses; s., supplied BY any Slowing
through the tuyeres into the furnace. When
place Q; the brickwork. to face the air cham
h hers with . riay or stoaewSrk peE9Irated With
passes direct to the chamber and instead Of
the heat OF the air passing off from the chsm-
beers. it may be carried away by pipes.
| writer in the Bericits gives an Interesting
account of some invest cations concerning the
cause OF the insolubiity OF pure metals In
acids. it being known that chemically pure
| zinc. rs also many other metals in a stute OF
purity. .are thus insolublc because at the mo-
become surrounded by an atmosphere OF con-
densed hydrogen; which, under NORMAL err cir;
from further attack on the part Of the acid. In
these most uniane experiments the amount Of
and Il va. 'e sousb
to be ascertalned what difference Would BE-
W When 'ha
the hydrogen would be greatly facilitated: the
rSs sas
made .d the scs
chronic acid, was INTRODUCED. the soubiiity
times and. wi en hydrogen peroxide was en-.
pIIoyed the ssolnbility was, Increased; The ex:
becomes attacked when the ordinary impuri.
ties are present is that the hydrogen is not
but rather upon Ii" more electro, negative i'm:
purities. In this way leaving the pure zino
Itself open to the continued attack Of the acid.
Some doubts are enter aimed as to the de.
STABILITY OF employing electric motors in col
licrics. One Of the objections which have been
raised is the possibility OF gas ex posion being
caused by spark occurring at the commu-
tntor. OF the motor where the electric cur
SStSfer qSbj;s,stioa i .hs We IN the III q
but cannot be kept in good working order
the dg nnf It is 4" Gssrf t TO
BLUSH sparks NAV he occasionally observed at
shs d f IN tr"psr the
machines. tho spark is practically non-eXist-
Ont under ordinary conditions OF working: it
Practically co"l"sS cool. indeed. tint It Is Very
difficult to cause 1t to ignite anything.
process Of coating iron with lead on zinc
has boon introduced at tho Wcstwood works.
Mllwal England. 1t consists in first picking
the iron articles TO be coated with lead in q
weak acid bath through which mild current
OF electricity Is passed: this looscns the mag
netic oxide or scala and cleans the iron. the
latter being next placed in a lime water bath.
all three baths having y temnernture Of i20'
Fahrenhelt The neg. step is;hat o. immers-
composed OF zinc and tin in equal parts. in =
s?lqtion OF hydr9chloric acid, al telnpernturs
through bath OF molten lead in the same war
as in the ordinary gal vRnizing process. and
this gives 1t the desired lead coating.
The wet" or orthochromatic process hns
for some time been successfully practiscd at
JafIe's Photographic establishment Vienna.
Austria. The main points In this method
consist In the use of eosine dissolved in alco-
hol. then cadmium bromide the solution being
afterwRrd filtered. after which Eulphuric ether
IL added, tho whole being finally, With re- psatcd