The sun., 1893-05-28
NOTES os SCIENCE AND 1SDusrnr.

} Among the various engineering investiea
tfons which for some time have engaged tn
attention OF mechanical experts is that hsvln,
In view some ready method for deadening tn,
Objectionable noise made by tho puffs from
tho exhaust pipe Of Gas engine. but onl,
IN Indifferent amount OF success hai
hitherto attended these Efforts. The mos
recent contrvance OF tho kind Is a de-
yiIce described in French Journal. and
claimed to be simple efficient. and lnox.
shi TO tSs esd o t
exhaust. with the split end UPWARD. and. be-
sds sgs Ss sna sn@ d Hs Gs cot IL. wns 5
out toward the top until It has a width .cnua
'S the pun n 'of pp s
spreads out like fan. aud the discharge into
produced depending somewhat on the flare OF
the tube.
| writer In the Metal Worker stntes that,
curious enough. tho cause OF what are known
as pin holes" In timed and terne platcs has
never boen satisfactorily determined. thou gh
one OF the many sources OF the difficulty
named has been tho use OF steel In the place
OF wrought iron. The interesting question
has been treated from various points OF view.
some urging that foreign matter in the steel
interferes with the picking and prevents tho
perfect coating Of the plates. SO that In places
aSrsded oorroson Rapidly cnsaes s"ea oehers .hs
again. arc OF the opinion that the pickling
ssae ssd remsns mai In the Of
after tho plato was coated. Ono Of the most
psnsible suggestions has been that tho aim:
tseli1that L is too ilne G grained m materai ter ief IN
comparison with iron. aud with a surface 40
for that superficial aloying which is supposed
by some to constitute the bond between tho
the tbrone nature Of iron. aud the somewhat
roughened surface. admits tho tin to sonk in
o tbs pn Th ihe Sgr n
tin plates Is considered ny many tho most
reasonable yet offered
An improved system. OF special appl cation to
artesian wells. and designed for obtaining
with low pressure Of water as a driving me-
dunn large amount OF power, has lately been
proposed. The machinery to be actuated By
this means may be OF my desired construc-
tion. but double acting pump works well.
tho piston in the middle pump being on pis-
ton or power rod carrying pistons in cylinders
near its ends. these cylinders being open at
their inner ends and ,connected at their outer
through which tho motor agent enters In
these chests slide cylindrical valves. their
rims rims orening anl closing The inlet and the
each central hub and radiai spokss to form
q discharge openng for the cylinders at
inlet p"rts the inlet over At 'nT ali
nmes n1n% , the Tlves are entirely surrounded or
san and "s pereety "Ssn
extending valve stems are pivotally connected
with transyerse piyoted arms. whose free ends
are ptvotally connected with each other by a
rod. and this rod slides In hearings formed on
arms secured 10 the power rod. the bearings
springs. having at their other ends colurs
aputting against collars secured to tho rod.
arms secured to the valve chesi. in OPERA.
ton. rs the power rod moves neeithor direc.
and then released. to force in one direction or
the other tho ROD connected with tho valve
anu Closing the ports In each chamber.
According to an account In the C,mptes
Rendns. metallic chromium Is now produced in
appreciable quantities by novel process. due
to the ingenuity Of NJ. Placet An aqueous So
luton OF chrome alum is prepared. to which Is
added an alkaline sulphate and q small guam
tity OF sulphurc or other acid. and this solu-
tion is electrolyzed; Mt the negative pole a
beautifully brilliant deposit Is formed on the
surface OF the electroie. and this deposit con-
sists OF pure chromium. Tho metul. ns do
biue-whi:e color: il /. found to resist atmos-
BY concentrated snlphuric acid nitric acid acid and
2 2. concsntrated M solution Of potash It appears
under certain conditions 1t is even possible to
obtain arrangements Of chromium crystals.
Thus the metal. which It is demonstrnted can
be prepared on practical commorcinl scale.
ana ao1n no1n r. OF
simi! lar to that employed as above. there WAS |
obtained an adherent deposit OF chromium OF |
a thickness variable at will and resembling |
and iron. Specimens OF this metallic chro-
MUM Weighing more than a kilogram. also |
exhibited to the Fronch Academy Of Sciences. |
Some valuable results in the production OF |
puddled iron have lately been achieved by IN
English manufacturer. and are explained in
dotail in the London papers. It is not often.
at the present time. that any special effort is
put forth for tho accom- plishment OF original
or improved methods in this Held OF metallur-
gical industry. as. owing to the advances
and THO extent to which it has super:
lhs latter have come to be of less impor.
tnnt consideration. 1t is now proposed. in
pudding arocess to me melt the BIZ BE IRON tt. TO
DO used in cupola. witt small quantity OF
scrap. and on the iron becoming LIQUID. it Is
conveyed to the pudding furnacs and allow ed
to remain there until It has reached the stand
ard degree OF heat In case OF any scarcity OF
ron M after leaving % ths eHpo,a. % 1t + is S Claimed
:hat by this means the output OF the pudding
furnace Is much increased.
Tho manufacture OF the beautiful fabric
known as cashmere Is characterized by some
oeculiarities incident to tho nature OF the
lbre itself. though but little known to the
Tearers OF that valuable material. nor. In
Iced. to many OF those who deal in the finish
I'd goods. A microsc opical animation OF the
cashmere flbre shows that 1t is composed Of
multitude OF miniature cells. similar in con-
'trustion ! to those Of wool. and these cellular
n tho process VI coloring. according to the
iature or strength OF the acid employed. An
'hnperiment II IN this linG Viii suffice 70 show
OF Of cashmere lbrss was elected promiscu-
'usly and coored In tho ordinary way: great
are was taken not to have AN excess OF
Icid: and. therefore. when the process was
complete and the flores dried and mRgnified. Il
WAS clearly seen that no harm was done. In II
he first tlbre the surface structure was in no
way injured. second lot Of flbres was select-
ID under the same circumstances. and sub.
nitted to q bnth In which an excess Of acid
vas present and the fbres being allowed TO
cmain the usual length o: time. were then
emoved. dried. and micros-opically exam