The sun. [volume] (New York [N.Y.]) 1833-1916, 1891-10-11
NOTES on SCIENCE AND INDUSTRY.

"A Massachusetts, inventor has devised I
douole-hulled ship, with compartments 80 ar
ranged and constructed that It supplies. he as
serts. o mathematical certainty against sink
ing. Between tho outer and inner shells OF the
vessel is a series OF longitudinal compart
ments to be filed with water. and emptied by
the vessels pumps for ballast: and above this
section. on either side. and rising to the full
height Of tho vessels sides. Is n series OF cham
bers filled with small ali. tight tanks. their ca
pacity being figured In excess OF the known
displacement Of the ship and cargo. Thus
o cubic foot OF air has perfect
supporting capacity for known weight.
It is claimed that with supply OF cir in
these tanks Of rs per cent. above that 70
mentery destruction could sink a vessel; Any
| probable collision. tho penetration Of shot or
tSe tsSH s
forming their work easily and SAFELY ely tn n1s
sscriflce involved in the arrangement being
decreased carrying capacity
An interesting problem In heat Ia referred
to by the London Engineer. In connection with
| Kirkaldy's arrangement Of heating feed water
BY live steam withdrawn for tho purpose from
the boiler. It appears that, purely with Wow
to save the racking OF boiler plates by the In
PRODUCTION OF feed water at temperature CON-
siderably below that Of tho steam and wator
inside. q novel kind OF foed-water heatcr
was oontrived. using fresh steam from
tho boiler for it in order to make tho feed
as hot as the contents OF the boiler. In do
ing this the matter OF economy was no con.
oss. IN view sHs .! tho izmpossb!ity ei
parting to the inaowing water all the heat OF
stss% s srfs lifted tS now
did the work with ten per cent less fuel con-
9umpti2n than they had previously rSIn II q;
never Wt he most esrea p ' Ipp
rs snaa 70 i5 With
By any ., tie laws q heating that have sysst
steam raising.
The rolling Of hollow staybolts is an indus
try recently introduced. and claimed to pos
scss special advantages. In this process. two
pieces OF iron. rolled In U-shaped section. are
laid together and wired In that position those
parts being then heated to welding heat and
run through rolls. and as the welded tube
comes from the rolls II passes over mandrel.
which fills the interior: before reach
ssn the .s ssoo1a s Of Ss m it s9
from the nandrei and the interior cleared, In
this way by Aye repeated operations, hollow
sry
Is sde saving sax
lpstesad q driing the ends Of the Bolts after
Tho singular fact Is stated In one Of the
textile journals that for years all the peculiar
cloth used In lining collins and caskets has
been made abroad The fabric used for this
purpose is like no other. being rather a cheap
grade OF wollen with q cotton warp. but fin
ished by some secret process which gives
1t face as soft and fine as the best
velvet. though with shorter nap and.
no matter how much it may be twi sted and
s eoan tods sRo Only factory
being consequently, held at a high price. Lat
cae stnd
method involved. the result Of these investiga-
tons being that at one Of the Maine factories
s ana i9!s m ee e
by experts as in every respect a most satisfac-
tory substitute for tho monopoly article.
"A recent French method Of sottening water
for Industrial purposes consists in employing
hydrated oxide Of lead. which prccipitates the
carbonates, srlphates. and chlorides. 1t being
necessary to obtain tho hydrated oxide Of lead
cheaply. this is accomplished by placing
solution OF sodium nitrate In vat. divided into
two compartments by diaphragm: lead cleo
trodes OF large surface are placed IL a solution,
sp%posed eaust iS' soda being formed IN
i dlssoIves certaIpp, quaptity Of lead.
passed through the liquid for, a certain time.
tho solutions are run from the two compart-
ments into second vat and there mixed by
oSde 81 lead ana s ssH FORMS sodu@
nitrate. the solution being then iflltsred. and
tre S On the lead Sxide becoming used up
1t is replaced by freshly prepared oxides.
Some valuable improvements have lately
been effected in the construction Of knitting
machines. tho new apparatus being provided
with unique quarter saver which prevents
the goods from running of the needless and an
automatic stop motion which stops the ma
chine Immediately. whenever @ hole or imper-
lection occurs or the breaking of thread on
any Of tho feeds: any number OF feeds may DO
used. according to the diameter OF the cylinder
speed Of the cylinder. causing q continuous
%tE S
vantage peculiar 70 this machine Is presented
IN shS Ehgn Il 80
yiled with a sectional cam ring. which can be
taken of II, sections for necessary, repairs to
noodles and Games. and one operative can run
five Of these machines.
In compromising locomottvesa new method
has been put into practical and successful
operation by the superintendent OF motive
power OF tho Mexican Central Railway. The
cost Of coal on that route being In tho neigh
borhood OF S11 per ton. the plan was con-
ceived OF diminishing fuel consumption by the
Introduction Of q compound syston. in which
the high pressure cylinder is encircled By the
low pressure cylinder; In this nrranRem;snt
In diameter. and tho, low pressure
diameter Of thirty and three.fourhs inches;
ono-fourth inches in Diameter. Tho strokels
twnnty-four inches and tho two rods OF the
l2w-pressu piston arc COUPLED with the sin,
gle high pressure rod to ono crosSlead. II
appears that In q competitive test Of twelve
trips with single engine the compound LOCO
ty.aye per cent,-ap important economy On q
road where the fuel account !s the largest item
OF operating expenses. being twenty-five per