The sun., 1893-12-17
VOTES ON scfnxcE avn IxDUsrnr.

II seems that recently, powdered metallic
arsenic. which. in tho process OF powdering
had been moistsned with water to prevent
| busting. exhibited the ecaDabillty-not hitherto
recorded-oi spontaneous com bustion. accord-
ing to nn account In a German scientific
paper. A quantity OF powdered arsenic had
been received in double paper bag. lAto
In the evening and set aside ovor
night in basket containing other
articles packed In straw and sawdust On the
following morning. upon opening tho store.
the peculiar Rarlic-liks odor attracted Atten-
tion TO the basket containing the powdered
arsenic. An eIsmination discosed the fact
glowing MAS. and that the paper containers
had been charred, nortlon Of the straw being
also ecorched. A number of bottles in the
bas kct had also burst owing to the high heat.
and ana npon pom ne Ghnrted pap.r bag were sub
lde. A fire. which probably would have been
attributed to some other cause. was in this
case averted.
Experiments made with tho water platinum
pyrometer on the boilers Of the Pacific mills.
Massachusetts. have exhibited some impor-
tant practical results 1t was found that In
the heart Of an anthracite coal fire the tenn
perature marked 2.421 degrees. while at tho
bridge wall 1t was l.34l degrees. s95 at the
entering tubes. and 373 at the leaving tubea
In this case. twenty pounds OF air were sup
piled per pound Of coal usually, however. this
amount being greater and having tho effect OF
reducing the temperature. The method uf
In a crucible placed nt the point where tho
temperature II desired, these, when heated.
being removed and submerged In water. The
weight OF the platinum being known, and the
weight Of the water. IL is ensy to figure from
the specific heats o. tho water and platinum.
ana the Increase In temperature the water
shows toy immcrsing tho balls. lust how nigh
the temperature Of the balls must have been.
The use OF hollow spars for boats designed
to attain great speed has introduced a new
and novel industry requiring workmanship OF
the finest character. The stick for this pur-
pose Is required to be Of exceptionally fine
and straight grain. and. after being roughly
shaped, 10 split longitudinally from end to
end; the centre Of each OF tho halves 10 then
followed out. and creator or less amount Is
removed. according to the intended location OF
the spar: the npper spars being much the
lighter; these hollows run nearly tho length
Of the spar. great care being essential to have
exsst to inaSfe f USS ihIsRnss. q, '@s az
every pont-oi course when this has been
T. circular hole I. lett ip the cen:
fss 2 tns pnnns M tine .ns whole
end After this the two halves are fastened in
MMsss MssGs ssn gan sy means St Of wooden dowsl
alternately on either side OF the central hol-
low. and both dowes and split arr, carefully
uONClb VARY III size with tn6 SlI0
Of the spar, but are usually as long as they can
IF s G
low than the outside. in order to give them. all
the length possible. In small spars tho glue
bands on the outside are added
An automatic winder OF cotton thread has
been contriyed a mechanism which takes
thread from eight large spools loosely wound
and transfar. II To eight small spcc!s contain
ing 200 yards; these small spools having re-
ceived 200 yards exactly. stop revolving. q
knife cuts slot In the spool. the end OF the
thread is fastened in this; the machine then
cuts the thread OF drops the spool into trap,
takes eight empty spools from as many hop
pers, places them on the .spindles and fills
these these as It did the previous .st. The ma
10 lust forty.hve,, seconds making all
changes changes autSmat!cally and with the greatest
small spools are placed on an inclined track.
and In rolling through the machine receive on
e esSn rea enG teEef cat trom long strip or roll
above the machine: Aftsrthe ticket Ia cut paste
Is rob applied % @ :" me hask and Il is then pressed
rosit ion to receive it-this at the rate OF ninety
spools per minute.
The subject Of obtaining higher tsmpera-
lures In steel furnaces has lately been dis
cussed by the Society OF Civil Engineers. Paris.
At present It Is stated, the temperature 10 linz
tied by that a. which the walls OF the furnace
begin to fuse. and oven Deeners frsbricks are
not found proof against this. Magnesis 10 |
claimed to be capable OF standing far higher
than that kind of brick. the prn-
cipal difficulty In using 1t being the excessive |
to which 1t Is liable when
hcated-a cube Of maGnesla OF ten-inch |
edge, in the raw state, Is said to shrink |
e. sIsrfIp Spe cofa,sa 81 saix,inSh edge when sum
furnace Innings made Of this material are La
bic 20 crack ha.lly asa remedy for this state |
rs ma ximlm possible contraction before be.
Ing placed IN the furnace, though for this an |
{ sexGessivsly high Temperature Is required; NJ. |
diniculties and has exhibited a number OF |
perfectly solid bricks y pagnesIa. which were
as dense as granite, and had been thoroughly |
shrgpk. The composition Of these bricks is |
I b42 % to aa25 DaRnesia, l.5O to 400 lime. |
90 silica
very Ingenious apparatus for measuring |
the intensity OF sound Is described in q Ger
man paper. A narrow glass tube bent at a |
very obtuse angle is half illed with alcohol;
one end OF tho tube has conical opening. and |
this is placed at distance OF 90 en-. from the |
OGening OF the resonator. the whole being |
mounted on board CAPABLE OF adjustment to |
any angle the pulfs emitted from tho re-
senator, when ,respo1ding 70 sound.
isr placements are read on on a scale attached |
% tho tube, projected, II necessary on to a
screen. In the observation OF that int egsstinR |
, Iert OF sound-repulsion-a light resonAt0r |
o the ordinary construction Is hoatsd on wa |
tor It's axis being Kept horizontal ny means of |
an attached piece ~ wire. and, on blowing the |
horn. tho sphere will oat In the direction op- |
posite 70 that in which the neck Is pointed. 70 |
produce continuous rotation, four resonaturs !
are attached 10 light cross Of wood turning |
On needle point or one resonatOI with four |
bent nscSs Is suspended by a thread.
Attention is called to the fact that for soma
lime past the superintendent OF motive power
1f the southwest system OF Pennsylvania lines
has been successfully introducing oil furnaces
N the various blacksmith shops along the
route. special feature Of this furnace is the
absence Of any stack or other means for car
-Ting OF the product Of combustion. II has
been found by experiment that on stack
being placed On such furnaces. the temperl-
ure cannot be maintained At as high a point
Is desired. but without a stack ths flames and
products OF combustion have tendency to
,Tssp out wherever thsTO Is an opening. On |
his account the doors in the front OF the fur |
laee are most carefully lifted, an additional |
F.a~. .W.sr rHa.F -EH4 "