, 1892-03-12

practically employed Was for the Ii hting
OF the Brazilian i%rOnclad, ~Aquidabal, III
1884. 1t is now used in Vienna, by the
Westminster Electric Supply Corporation,
by the Notting-hilI Lighting Company, and
many other societies. The stations using
these dynamOS rave in practice obtained
the reputation oil being The most economical
of amy IN the world. The average cost
taken from six London stations using
CIOmptOn's machinery, OF producing the
Board OF Trade unit OF ! 900 volts al hour Is
reduced to fraction below 2dI so much
for one great leap in the march OF progress.
The electric crane, too, shown III tue
North Nave is an object of great interest.
1t is like StephensOn's Rocket" the hrst VI
its kind, and from this model a number OF
cranes have been made for hosting In tim.
Der yards, railway stations, aud whArves.
This crane is made 20 lift ton and 1t 'SlewS
and travels at the same time, and az there IS
no fire employed with it all danger OF con-
fagratiOn is avoided. Insurance companies
have already welcomed this form OF motive
W and reduced their premium accord
ingly. 1t il said hat a SIMILAR crane to that
shown has been at work in an East-rnd
timber yald for some time, and that rate
OF insurance has been brought down by Its
use from 30s. to 12s. Sd. The CronlptOn
crane is driven by electric current trans
mitted through two conductors into an
electro motor fastened to the winding drum
Of the machine, and the mechanism is so
simple that a child could control the ac-
ton. Now let us mount another round OF
the Giants ladder.
There has been u noteworthy development
Of engines whether driven by steam, or
gas which can run in dire l-coinection
with dynamOS without the intervention of
a belt or band. 10 draw Il commonplace
sinlle, the ~Self-ConpeCted engines can be-
won ked in a COal-ctllar, the belt connected
tStill much iavoured i'll Germany require
he accommodation OF a special shed. In
iaCI a modest greenhouse, not the Crystal
Palace, is needed to put things 'Ship-slG pc.
Whether by good luck, on good manage
mCHt, or by q continuation OF b, til. a CAPT
tai illustrate ion Of the Il ference bel on ISL
ana present is To be seen in the NV M
chincry AnneXe at tIe Palace. Almost 0p-
pOsite 10 one another are specimens of botn
bent and col l%uncIlvr englm.. Stretching
over many yards OF space is a fine q .lowly
bel - used for the GrIcher lighting appa.
latus an the nave. 1t makes seventy re-.
vOlutiOus a minute Its riS-d-Ois is a llttle
Brush OF 20-ho,Se power, which makes 800
revolutions Il mlnutC, with brelhten of
50ll.p., 75.h.p, dnd 2oO-h.p, the latter re-
vOlNIng 100 times IN the same space. II
should be noted that in this respect the
greater the size, owing to weight and
strength, the less the speed. DwaItS often
do more laOOur than giants. In 1881 scarce
" any special machines were CONSTRUCTED
a CONVEX ted steam engine did duty in MOST
cases, and such new forms as were brought
oul were mostly crude, nnteSted, aud often
incapable. At that Time HE GALLOWAY"
mentioned above, and specially inSta led 10y
the Crystal Palace Company, was consider
ed the acme of perfection. Also. be it IT.
mcmbered that to-day special dynamoS for
higlI-teISiOn pressure are very much cheap
er. probably by reason Of perfected crafts
manship. One OF the latest improvements is
Suckers patent hi2h-speed engine, now fOI
IL, fin st time exhibited by Messrs. Easton au0
Anderson, OF London and Firth. This light
and admirable machine, of so. brake b. d.
works at Il speed OF 400 revolutions, and
has an economic steam distribution, secur.
ed by special arrangement Of cylinders and
q sensitive governor" acting directly on
the cutoff valves. Strong and supple, it
MOI cover possesses the advantage especial
" valuable on shipbOard, Of having tev ry
part of its frame uaenclosed. Prehtice's
dynamo OF the Paccinolti type, also shown
by Messrs EastOn and Andvlson, is, dis
tinguished for the magnetic density, which
il SO great that even at Comparatively SLOW