New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1895-04-15

generating electricity. and hence TO revo.utionze
that art. Several specimens OF this device diner
.nc among themselves In form but not in principle
were publicly exhibited and explained by MT Iesia
nearly two years ago. He has since Improved II 10
detail with n view TO still greater simplicity ana
efficiency and 1t Is said that just before the hre
which destroyed his laboratory a few weeks ago
this invention had reached such degree OF pertec-
ton that II was ready for the commercial stage Oh
It's career. Although some Of It's Jess important
features still kept private. and while II IS In,
possible yet to measure with accuracy the possioi-
ies OF its usefulness the oscillator Is just now at
tracing renewed attention and provoking much en-
thusiasm among electrical engineers
The fundamental idea OF this machine Is that the
coils OF wire IN which current Is excited are
moved to and fro horizontally. instead or beins
whired around n; a rotating shaft What cleo
tricians call the field" is the in front OF the
poles or pole pieces OF magnet Out into that
space there extend invisible lines Of force IL
piece of soft iron be moved transversey past these
poles and them, cutting the lines OF torce' II
IS momentarily magnetized by induction; ana IN
any coil Of insulated copper wire surrounding 1t
there IS induced. for the same brief instant. an
electric Impulse In the ordinary dynamo a ring or
soft iron is ussd instead Of bar number OF con-
nccted coils are wound on II. and the whole arma-
ture H. revolved between and in very close proxin-
ity 10 the field magnets; but Mr. Tesla WINDS ms
coils on straight bar. and oscillates the latter be-
tween his magnets by this change OF method, he
Is able 20 accomplish several things not secured by
the ordinary dynamo. lie reduces the size OF the
apparatus greatly. The steam engine Is SAID 10
weigh from onethirtieth 10 forte III much as
any standard type Of stationary engine having the
same steam pressure and piston speed; ne gets ria
of governor ny-wheel eccentr.cs. cutoffs, packing
and other "jg-a- rna-rees': and with the same
amount OF steam he generates about twice the cur
rent obtained FROM the old. cunIbrous. complicated
and more costly machinery.
The outward appearance OF one OF the early oscll-
lators is SHOWN IN the frs. illustration and the gen
eral Arrangement Of parts in the second The cores
OF the big field magnets are indicated AT NM. and
tho insulated copper wires wound around them at
" " W W The pole pieces. T. p = p attached to
,he ends Of the cores extend the magnetic fields 10
the narrow gaps. II H. At these points are placed
small armature coils wound upon the shaft A. which
latter sides In the bearings u +. under the nilu
cncc OF piston screwed on 10 II. The walls OF The
,vl,rIer g C. the Jacket J and the inlets II tell
their own story and the further details need not be
oxpl,ucd In the model hero represented. COM
pressed air was used Instead OF steam but the lat
ter is 10 be employed IN the perfected osciliator
The motive fluid. whatever It be, sniites the two
sides Of the piston alternately. very short stroke
results In some If Mr. Tcs.a's models this ranged
Srom -s!Xty-fourth To three-cighths OF an inch
But this movement Is enough to excite brief cleo
trlc impulse In the coils at II H. whence the alter
mating current is led OFF TO its work. without the
Intervention Of a commu;ator. This last improve
ment in Itself great gain. 10 say nothing OF the
other merits already mentioned. Besides. Mr. Tesla
claims that I'm his machine there is no uie ~He' DIS
in the rotating system.
one Of the mos, eSqusltey beautiful as we'll as
essential features OF the osciator Is yet TO be
mentioned Il is desirable that the frequency OF the
alterations I'm a cuIrent-s period, as the experts
ca. it-shal remain constant in the face OF all