The sun., 1896-09-27

The use OF hollow shafting instead OF solid, sp-
peara to be gaining in favor, the principle, OF
course, not being new, bat mechanical dif1oulhes
presenting themselves in certain applications.
For instance, pulley 10 sometimes fastened N
shaft by means OF q bit Of metal called . key,
wedeed in between the two, slight recess or seas
being cut in the shaft and the inner surface Of the
wheel to receive IT, and thus, long az the shaft
10 solid the key can be driven inward without spe'
ciai care-if, however,, tho shaft werc hollow, 10
might spring slightly under the pressure, and its
shape be to that degree distorted. But the fact ia
now coming Is be recognized that screw clamping
bolts, running rndlay inward from the hub OF .
pulley, will grip the shatt firmly as . key-the
latter, being pronounced needless by experts.
The results OF some valuable experiments on the
fabrication OF machinery bearings have been set
forth by Mr.. Dewrance, in an address before the
Civil Engineers institute, London. His observa.
tions show that olive oil becomes black and thick
after passing through the bearings several times
this oil. after filtration, composed Of 10 per
cent. of oieate of lead, 9.b7 per cent. of oleate
acid, and 82 per cent of olive oil and glycerno
the oleat aciu in the olive oil appearing to at.
tack lead. zinc, and copper with great activity
thus. disks of metals used In tho manufacture OF
bearings were immersed In olcate acid, occasion
ally drawn up cut of the ncd to be exposed to
the air; lead and zinc rapidly corroded away, cop.
per was corroded TO less extent while tin and
antimony were not approciab'y affected. In re-
gard to the compressibllity Of alloys, it 10 sug.
gested by this authority that alloy be used until
II is satisfactorily demonstrated that its point OF
nrst yield Is considerably above the greatest load
or shock to which It will bo subjected in use. In
testing the effect upon soft metal bearings when
the shaft sustained a heavy pressure, piece OF
iron found to leave no mark upon surface
softer than itself.
cIa aoune time forth " Paul d. 'Humy.
q French naval ofI1cer, of having originated pro-
cess for the successful solidihcaton OF petroleum
fer commercial and Industrial purposes, has been
further explained by him. From this account.
summarized In the Progressive Age IL appears that
heavy common oil has been converted by this in.
ventor into q solid block as hard as the hardest
coal-burning slowly. giving Off an intense heat.
and showing not tho slightest sign OF meltng-a
ton of such fuel representing as many as thirty
tons of coal. and the space occupied by one ton of
II being about three cubic feet against the large
space required for the coal. AT recent gathering
OF experts, NJ. d'Humy exhibited samples OF the ar
ticle and experimental with them. ON the
table were several cakes of the solidiHed petroleum
and of low grade oils of various sizes and
shapes, and In addition to the cakas there were
samples OF the same fuel In dry powder and pastei
the petroleum powder and paste mixed together
and pressed forming a homogeneous mass. with a
great specific gravity. hard almost as stone, and.
times Its own volume. and heat we'll nigh as
great as oxygen. Tests to determine the prcduc.
tion OF smoke smell failed TO indicate the
emanation OF either OF these.
Photometric comparisons OF the intensity Of the
light from two windows similarly situated, one
glazed with plain glass and tho other with
ribbed glass, show q difference OF so to 200
per cent. In favor OF ribbed glass; the oharac.
tcrstics of the latter. as explained. being thick
ness of eighth inch, with twentyone ribs TO the
inch and nearly coloress. The definite result in
this comparison, as presented, was the transmits.
sion by the ribbed glass, with ribs horizontal and
in direction perpendicular to its plane, of 80 as
much plain glass; and in q direction thirty de.
grees to the right and left, 2.6 times as much as
plain glass; and in direction sixty degrees to the
right the left, 10 times much light as plain
glass The action of the ribbed gass.appears to be
prismatic, the greater part OF the light falling on
that at any point refracted ana spread out into
fan. shaped beam lying in plane nearly perpen.
dicular to the plane of the glass and to the drec.
tion OF the ribs.
According to DR.. james Croll's estimate. the fee
sheet ut the South Pole is at this several miles
In thickness its upper surface being above the line
of perpetual snow, and therefore not capable of
melting away during the warm eras succeeding
glacial periods. Further when such an enormous
mass Of ice is again incrusted about the earth's
in the process of tine. the consistent supposition
is that as as II begins to yield once more to
the influences OF q milder atmosphere, as Its
counterpart did long ages ago, the same process
of flooding great of the earth will be repeat
ed, and the same remarkable evidences Of the
presence OF and oceans that no longer endure
will be left behind. The theory entertained by
Alfred r. Wallace is much to the point namely,
that as past glacial age melting into the ter
tary period, the seas in the northern hemisphere
covered much larger area than now, and extend
| ed across central Europe and parts OF western
Asia, and the Arctic Ocean was likewise enlarged.
| 1t is well known, by geological evidences not ad.
mitting OF any question, that the lowands of
Europe were submerged and that the Baltic, Cas-.
| plan, and neighboring seas were simply part Of
the vast Atlantic Ocean, instead of being land
locked waters as they are now.
The London journals pronounce the Blackwell
tunnel-to open communication between the sections
north and south of the Thames below London
bridge-one of the greatest engineering fcats of
century. Especially noteworthy is the cutting
shield for boring, the largest ever known, being
nineteen and one. half feet in length and weighing
| $50 tons. This sheld was huilt above ground and
then transferred the bottom OF the caisson, the
| transfer being made by first making tho shield
water tight, and then cutting dock in the ground
sufficient float II; the dock was connected with
| the casson, which had been previously iilrd with
water and the shield was hoaed over IL into posi-
| uon the water then pumped out OF the caisson.
the shield going. by virtue of its own weight d.
| rect to the point for making the FRS. cutting.
| There are four caissons, two each side of tho
| river varying in depth from seventy fve to ono
hundred feet and each caiason is of wrought iron,
| nrty eight feet external diameter at the bottom
and forty eight feet internal diameter Throughout;
| they are made of two skins OF wrought iron,
each about three fourths of an inch thick, and hve
| feet apart. braced together and filled with con-
| crete and built above ground and sunk by exca.
| waiting the earth by manual labor, the weight of
| each mounting up TO some 5000 tons.
| Quite a useful mechanism has been brought for.
| ward in the inventive field by C. N P1ckworth,
| Manchester, England. namely, a power computer
| for readily obtaining, without calculation OF any
| kind, the brake horse power, the indicated horse
| power, and the mechanical efficiency of engines.
| Although primarily designed for power caIouia-
tons OF gas and oil engines IL is said to be equally
serviceable to the steam engineer. while not n.
important additional feature is the ready sol ton
which IL affords OF all questions relating to the