The sun., 1897-09-26
VOTES ON sCIENoE AND INDUSTRY.

Amethod Of preserving boilers not in use has
been prescribed for the French Navy. Accord
ing TO this the boilers are completely filled with
fresh water, and In the case OF large boilers with
large tubes, there is added to the water certain
| amount OF milk Of lime or a solution OF soda
| In the case Of tubular boilers with small tubes
| milk OF lime or soda is added. the solution, how
ever. not being so strong as for the larger
tracing thy effective area BY deposit from the
solution. The strength OF the solution Is TO hc
s%'' the MH,n S Care een."sS sSomGj GStdS
ia taken en-, to preserve the outside Of the steel
| TO DO used for long periods; such are for this
purpose painted With red lead or coal tar AS
FAR 8 Is possible TO rc'ch, while for those por-
| tons which are inaccessible IA protective coat
Ing Is obtained by burning under the tubea a
certain amount OF tar or coal tar, the. smoke OF
the air from reaching The suriarco the tubes.
Besides this treatment, the boiler casing, is
has been placed inside. Periodical Inspections
OF these boilers are made TO insure the complete
| filling OF the tubes.
1t is an interesting fact in the records OF
scientific progress that the United States Navy
has for n long time past been dropping bottles
overheard in tho Atlantic Ocean at the
| Azores, in deep water along the coast of
Spain. and from the Madeira and tho
| Canares southwark along tho const of
Africa. The fact that all these bottles that have
been recovered have been found on the coast
q South America, on the Antilles, and some of
| them as far west AS the mouth OF the Rio
Grandc suggests the Inference that every buoy
| ant object which has teen dropped into tho
oe or SSls eTHh
| tuRuese or fricans has round lis way TO Amer
tenth parallel south and the thirtieth parallel
north. In the northern part OF the Atlantic
Ocean Gear the currents run the Other way and the
| Europe. In the Pacific Ocean the daily mails
| delivered on the west coast of America from
bout the twentieth PARALLEL north, in The vioin-
ity OF the Malay peninsula and nrchipelngo.
and the Japanese Sea to pick up matters de-
signed for the western hemisphere
! A circular percussion table OF peculiar mechan-
ism is in operation at the Argent mine, Tasma-
MIA. the machine consisting Of a cast-iron table
thirteen feet in diameter. convex in form. turned
smooth on the surface. and vibrateu by cams
| worked by n shaft underneath. The separation
Of the minerals from the gangue is by means Of
water currents supplied by curved water pipe.
| revolved slowly over the surface OF the table,
receptacles at he outer rim OF the table recciv-
| ing the several gr .des Of concentrates. The ore
| Is fed onto the table with water and runs in
curved dIret tion toward the outer edge OF the
bic; On its way the stream 10 re iuccd in velocity
and depth to about onethirti, owing to tho
greater surface covered. causing n separation Of
the lighter and heavier PARTICLES the former
| leave the table at on,e, while the latter are
| further separated by passing under the stream
! OF water from the rotating curved wafer pipe.
| which, assisted by the vibrations OF the table
with gradually increasing energy and velocity.
| separates the various matcri ais according 10
rotating delivery rcceptaclcs. and thence into
circular troIsns which collec the different
| from twelve to fifteen tons.
Quite an ingenious device has been contrived
| by I. W. Haley, a well.known mcchanican In
Milford. Me-. viz. s.lf-lubricating bearing.
.,l, ,t ball,
to anything yet proposed in this line. 1t con-
| sists Of a compound OF metal and graphite COM
| bined in such manner as to hold the graphite
| In solution. this latter fe ture being the chief
point of originality in the invention. An the
I mctals that are used fuse at Il much lower
temperature than, will vitrify glass. which
REQUIRES 1000 F; The metals employed
form. and combine before the glass becomes
liquid, and are then pressed into The journal;
and one which cannot be melted out by any
friction that could occur. as il will stand red
M,h es. o S'hs me M Mh6, 'q%rn hs' h WI run
brittle. The Haley journal is maize of glass
lead. and @ @EIaphlIc: which ecures selflubrioe-
and for large shaft:ng powdered aluminu UNI and
brass are added.
According to paper recently read by M.
Lavezzari b, fore the Paris Society Of Civil En-.
Eineers. the systcm OF traction by means Of
compressed gas MISUNDERSTANDING at Dresden
anu subsequently operated IN Other European
citics-is peculiar in some respects. when COM
pared with other attempts Of this class. The mo-
tor used is OF the ottotyp having two cylinders,
and located under he seat on one side OF the car.
For iEnit OH electricity is uscd. and to change
speed or direction gearing is employ cd; |;
VIII. The speed lever and reversing lever
and when the former is in OPPOSITION the he
engine runs free. though. US at the me time its
gas supply is throttlcd its speed I'll, to eighty
revolutions per minute: flushing the lever to
rig or lief, places ei her the high or low speed
in gear with the -nG nc. simultaneously fully
TO run at its normal speed OF 80 revolui ons
voirs. two OF which are fixed under the opposite
seat to hat connecting the motor; hesc rcser.
are charged iniiiaIly TO a pr. ssure Of lao to 20
pounds per square inch The cooling wAtor Ia
Ia" compression stations Il small gas engine ia
used to drive tho pumps which charge rcscr.
yoirs connected TO . stand pip" nenr the track,
connected TO this and the valve opened.
Attention 10 drawn by the Boston Jorr nal O,
Commerce 10 some recent improvements made
abroad in extracting ibres from the various
hbrous plants OF the class KIN wn r"mie. rhea
or China grass. The inventor in this case
whose name or location is not gvcn-has found
that by the use OF acids, AS hitherto empiol ed
such hhrc' nrc reduced in strength or caused tc
decay. thus rendering them prac ticaly useless
for m1nur"cturinr purpose. To overcome hi.
and other objections. tho method now
,roposct includes provision for a mum
rer of baskets, made OF galvanized wir" OF
other suitable material. TO hold the fibre
In place; and the next erutinn Is {,
place su ic 'nt number oil these baskets, after
their hnvug been tillui with the raw rbrc. in a
high'prcssurc kier. now in common use. Having
, covered he b'skcts with water. and added the
, chemical ingredients. conosl ,ng of two or more
Of the following, w. soap, pure "khi, pc
troi nm oil. nj hiCnrhonntC OF sofa. after Tho
klcr is made tight, 1.-Two ste. IN is forced in and
allowed TO work ny to ant at MY I" ,hry;hyc
r"nnrs per square men ior - suitable length Of
time. usually from four 10 five hours On this
being accomplish the hhro ~ ready to hs
taken out md wWsh"d For future Opcrntions
this process Is claimed 10 render special service
Another method OF r"prootIng wood has been
brought forward-th,s time at Huringl am
where the British Non-inhtmmnblc Wood Com
pany has given an exhibition designed do
monstratc the security az inst fir OF buildings
constructed with timber treated by their new
process. For The purrosc oC The experiment
TWO buildings about eleven feet s,IlI ,ru n nd