The sun., 1893-07-16
NOTES US SCIENCE AND INDUsrRH.

the Austrian Society OF Engineers. Some 216
mechanical tests wore made by tho COMMITTEES
having tho matter in hand to determine the
quality OF wrought iron. OF basic. Bessemer.
and basic opcn-hearth steel. the conclusion be-
Ing that the latter excels all the others In re-
sistance to mechanical attack and distortion.
Tests we're made on lattice girders OF 80 feet
i inches length and 3 feet IL inches depth.
the whole number OF girdcrs tested being ten.
vlz four OF basic open. hearth steel two Of
basic Bessemor. and four OF wrought iron,
some some OF the latter being Styrisn iron.
inches ranging between ~ and 2S per cent
The = -RSohemis9 S iron used had ten sie trenets
per 70 cent Ths h0b"ds S"a me SI
was was chemically good in quality. and ranged in
with ans 81 cent Rouha n:
basn basic Besssmet tn 5 showed extremes o. $4,000
d po%uds %h W Wiz PER sspt eonssSS so, end
wthstanding the fine quality of the Styrian
iron the committee gives, a decided Iretetence
steel the dimculty experienced is in produce
Ing uniform material. and the steel 10 also
sensitive to surface injury.
NJ. Eillon. In q communication to the Gents
C,rR on lighting aud heating by heavy hydro
carbons. criticises unfavorably the usual
methods rosorted to in tho burning Of LIQUID
fuel He is OF the opinion after careful invss-
tgation and research. that the conditions to
10 fulfilled for obtaining complete combustion
with such materials are essentially the follow
ing: First o division Of the burners SO as to
obtain q number Of Jets OF flame. between
which tho air may arrive In sufficient quantity
to insure the perfect combustion Of tho carbon
ana ana hydrogen contained 1T in the fuel and. SEQ.
divided Stu combustion IN question. on 2 large
points where combustion takes place. by
means Of this arrangement the flames cannot
disnssociation is prevented. and. indeed. tho
tempernture OF propagation Of the inilamma-
ton or ignition need not be exceeded.
very interesting paper has lately been
read before the New Zealand Institution Of
Civil Engineers on the subject OF heavy rock
blasting-Eranite. gneiss. and limestone-in
large blocks It appears that in somo recent
operations on an extensive scale for public
works large blasts were employed. the rock
varying from bedded and iointed gneiss to
homogeneous masses OF granite. and. on an
average. one pound Of dynamite dislodged ten
tons Of stone. the total amount OF charge be-
Ing usually decided on this basis. Tho separ-
ate charges were proportioned In the ratio Of
the cubes OF their least resistance. and this
latter was divided by. 81 for dynamite, SO for
geleGnite. ~ for eclatine dynamite. 80 for
explosives and another OF seven tons were
much. II was found that charges of from
Sroed 9rs.t9urth tna n ton to one and half tons
answers with a line Of least resista nee exceed:
ing forty feet; beyond that. the elasticity OF
the ns Ss
the explosion may merely develop an undulat-
best results We're obtsined where he" V the rock had
ono or moro loose ends with q nearly vertical
ing usually nrst removed by hand blasting be-
i9Te ais ririnG the large shot The length OF the
head as prscticable While let tn" % most % even D'r re-
suits n were obtained II fifteen multiplied By the
he fS ehe Tth
frregularly shaped blasts.
The efficiency OF the compound locomotive
used on the Old Colony Railroad is stated In
the Providence Journal to have been much Inv
creased by improvements due to the ingenuity
OF F. W. Dean. the inventor. The intercepting
valve Is placed on the high pressure exhaust
pipe. where 1t branches from the two parts OF
the receiver. The converting valve is intended
to be placed on the high pressure steam chest
cover. and is connected to the intercepting
valve through tho openings. the arrangement
Rsins smilaF to that but
When steam is admitted to the high pressure
at tie same time. BY means Of the
and the connecting pipe. steam Is admitted 10
the top OF the interceptine valve through the
closed the openings are uncovered. steam be-
Ing thus admitted to the receiver. and thence
the loWes cylinder When th
interceptine valve increases sufficiently 1t acts
upon upon the = ,p top Of the eonyertinG valve and
steam to the receiver and low pressure cylin-
der. and the intercepting valve is then lifted
nular space Of the intercept!ng, valve: tho
starting steam which held the valve down 10
at the same time exhausted into the air.
A marked success is reported to have at-
tended the substitution OF steel or iron for
mine timberinG in England. According to tho
report Of the President OF one OF the most i'm
portant coal companies. the adoption OF iron
props and steel girders was initiated somo time
ago on q main road 10 feet wide 800
Yards being secured with such props and
girders. and covered with three -eiRhths-inch
boiler plate. the girders being set about 3 feet
apart. This was done six years ago. and. as
yet. not q single girder has been taken out or
rhe r 95 main
BY 3 inches by, 3. The cost Of ono erder
and 80 square feet OF three, @ @eighths-ncS
boiler plate. is estimat at about So per lineal
VI running DuEu. WHlle securing tue same
area with timber. the cost would be- from 81 so
9 So per yard. Thus. though the first cost q
steel and iron Is nearly three times that OF
ordinary timber. tho life Of the former is esti-
mated as a, least six times that OF the latter,
sidh the adyaPaGs ;s nso 3t SAYING the Labor y
,toppaces during working hours. and. again.
when u road Is done with the materials are
IT'LL serviceable for the same purpose or Sal.
able as scrap.
The latest device in the lin OF boring ma.
chimes is one that Is being manufactured Ia
'incinnatL which Is said to bore all kinds
II straight or angle holes for car and bridge
work with the greatest rapidity and ease for
he operator. There Is one single column.
With the main roller frame resting on and
'olted to tho same: the vertical part OF tho
column Is made to reyolve tho centre OF which
5 the centre Of tho mand el: it is also made
o move In and out on tha main column. like
Eise CARRYING the spindle and slide moving up
md down on the same operated by hand
yhOel and RcraX. Tho rolls ara ELK inchAa