The sun., 1895-02-03
NOTES ON SCIENCE AND IND USTR 7.

NOTES ON SCIENCE md INDUSTRY Y
] French chemist claims to have proved that
| on burning in air equal volumes of coal ga:
| anu OF hydrogen, the same weights of nitro
| gen are converted into ammonia, and that
on burning equal volumes of coal gas and
! OF hydrogen. the nitrogen transformed into nj.
trous acid will also have approximately the same
weight: but on burning carbon monoxide, nearly
| two and one-hRlf times more nitrogen is found
in the state OF nitrous acid than in the former
| case. In the burning OF one klogram of each
| of these gases. IL is stated that the most
nitrogen in the state Of ammonia, and In the
state Of nitrous and nitric acids. is found in
| the product of the combustion of hydrogen, only
| one-fourth of the quantity being found in the
| case of coal gas, and about one-twentieth in
| burning carbon monoxide. On burning wood
charcoal In air. whether merely dried or heated
| TO redness. the quantity Of nitrogen contained
IN the nitrous and nitric acid collected is said to
be almost equal to that OF the product. and there
!. not much difference In the result of burning
| an equal weight Of coke 1t is remarked that
| the formation of ammonia during the combus-
ton of coke or charcoal is merely result of the
decomposition OF these substances and thus the
weight OF the ammonia formed varies according
to the degree OF heat.
The announcement recently made of a Ger
| man method of producing glass which will
transmit light freely, but not heat is founded
upon the following statement OF details, pre-
sumaoly from the source of operations: A plate
of this material. four-tenths of an inch thick
containing 2S per cent. of iron in the form
described as ferrous chloride, allowed only
400 per cent of radiant heat to pass through it,
while another plate of equal thickness. and con-
tanning quite as much iron as ferric chloride.
permitted 11.2 to pass. The chemica, dis
ttncton is exceedingly small. but the
effect is very marked. Using oxide instead
ferrous. condition. one per cent produced
a glass having very faint b lue tinge. but even
layer .aas inch in thickness allowed only o.
per cent. OF the heat from bat's-wing gas
aPsd To buass pass .hSGpg 9a Of h
light: but II would bansmit twelve per cent. OF
heat from sunlight. ordinary wndow glass, on
the other hand, letting some oghty-six per
cent. through.
A description is given of the Swedish method
of manufacturing matches, which has at
least the merit of simplicity in the manipula-
tion of the wood stock. The timber is cut into
blocks about fifteen inches long and placed in n
turning lathe; with each revolution a slice or
veneer is peeled OF the thickness required for
the match sticks, while at the same time eight
small knives cut the slice into seven pieces like
ribbons. and OF the length required for the
sticks; these ribbons are then broken into
lengths OF six to seven feet knotty and defec-
tive pieces are removed. and the ribbons are
then fed through II machine which cuts them
into pieces ike straw cutter, these then passing
through an automatically arranged machine
with cutters which slices Off as many rieres rho
thickness required for u match, as there are
cutters. one machine turning out from i, ,0O0, 900
to 10 900. 900 match splints n day The data
given OF this manufacture shows that Swedsn
and Norway have long been among the larunst
mattel h producing countries OF the world their
exports amounting to about 10000. 900 pounds
mum ber OF factories is stated M 300 VII an an
and in Rnstria t%ers oI" so ta,enGs,
with a corrcsrondingly large output
ihe bertrand process ior coating with mag
hetio oh'"' anu ehame'''ng IRON and iron car
nus oeoi eA p'''hea peiore the feris So
.''o ''nSou'asc'heh'. ihis new process, II
appears Is onsea on an interesting discovery In
chemistry as GAINED by NJ. Bertrand namely,
that IL "a thin, adherent film OF unotLcr metal IA
formed nm wrou,ht Iron ,, ,os, 49,, 49,, -
" s"' ''oh vi '"st Iroh' anu TINS
iron or cast iron, heated to 000', be posed To
a current OF oxidizing gas the oxygen pene-
trates throuvb tho f,r, and oxid,,o. ~ -
e touH '"' MN anu "N'u'|eS lhe IRON or
the cast iron, the result being magnetic oxide
The formation OF magnetic oxide Tins obtaIrcd
continues indefinitely, aud the thickness OF lie
oxide coating Increase. nrcoriiny IN tba nsrinJ
OF exposure to The oxtdisinr curreni nronridinH
the temperature remains al nIrut / 0Oos lila
him of metal deposited in the nrst in:,nn"e
disappears in some obscure way fnrn,in,, ny iI.s
which muEo with the magnetic oxide or
Volatiize, according To the nutura NJ thr ni,etai
OF which they are confessed In hi, ii,ye,Iiy"A
tOns for the best method Of druOsitin,, ,, Sho
article To be coated A. n,rrTntd III ,ns
that bronze a mixture of bronze and lin NuIyr
the desired satisfaction. The article is ciruns'd
ing a solution OF suinLnuLrunt, ~ S,',,,, i
tin; and, the coating of bronZc Isin,r fnrn'ai "i
the article is immediately washed viii cNii
water aud dried with sawtust. then put into