New-York tribune., 1896-01-13
EDISON'S LATEST WORK.
HIS MAGNETIC SEPARATOR.
AN INTERESTING MECHANISM FOR HANDLING
CERTAIN IRON ORES

during the last few years Several devices emoody-
ing this principle have already been patented ana
put in operation more less successfully. The most
conspicuous worker in this field. however. has been
Thomas A. Edison. who has been busily engaged
in perfectng the process In the vicinity OF large
deposit OF in Northern New-Jersey. At
place formerly known Ogden. but now caiied
Edison, operations have been conducted on large
scale. An extensive assortment OF machinery Tor
drilling and blasting the rock to depth OF thirty
feet below the surface, scooping out the material
thus loosened. and crushing 1t until 1t is as fine as
granuated sugar, has been set up there II Is pos
sble to take out least 900 or 5000 tons there
day, and the crushing. conveying and separating
apparatus is said to have a capacity OF 1000 TONS
In a vague way 1t has been known that Mr.. Edi-
son had encountered certain difficulties in the app-
cation of his theories, but these are now reported 10
have been overcome Some OF them grew out OF the
enormous quantities Of dust developed during the
preliminary treatment OF the ore. SO hiled was the
air with minute particles of grit and dirt that the
workmen could not breathe without wearing muf-
ners over their faces This they continue to DO But
the nuisance has been largely abated by surrounding
the buckets carrying the pulverzed ore with the
coarse bagging commonly called buraps. Another
problem related to the ubrcating OF the bearings OF
the great crushing rollers some OF the latter peng
designed 10 chew up rocks weighing ten tons each'
Mr. Edison in this and other parts OF his establish
ment, would tear very expensive appliances
which did not work right and replace them with dlt-
ferent ones and 1t is said that plant which could.
with his present knowledge. be reproduced for sooo,-
900, has cost him up date about five or SIX times
that amount.
The general plan of separation by means OF mag
nets is to let the powdered fall so as TO pass
very close the ends poles) of several horizontal
magnets. Those grains which are made up chiefly
Of iron will be attracted by the magnets ana
drawn inch two to one side or me
path which they would otherwise follow and Will
be held temporarily. sticking to the poles. while
the purely stony natter. insensibe to the influence
OF the magnets continues to drop. To perform this
service eectro magnets are used-pieces Oh iron
which derive their magnetic qualities from cur
rent Of electricity sent through coils or wire en-
circng them. and devoid ef any attractive power
as soon as the current ceases. In Mr. Edison $ ar
rangement the downpour Of ore Is checked every
five seconds. and then the current Is shut on, so
that the particles OF iron temporarily attracted 70
the poles OF the magnets released. Ihey faiI
on the other side OF a thin partition from the non
metallic refuse and the two go out through diHer-
ent chutes and are carried off BY separate convey
ing machinery. Inasmuch as the frst treatment
by this method does not extract all the Iron from
the ore the refuse Is exposed a second and third
time 10 the influence OF magnets, the three opera
tlons being conducted on separate floors The
amount OF iron (or rather oxide OF from original
ly In the rock and remaining unco.lected by the
magnets is estimated at less than per cent
An electro -magret may be made in great va
rety OF shapes. Almost every one has seen the
long fiat strip OF wood around which, from END
TO end a fisherman sometimes winds his line. Mr
Edison for reasons which will be apparent on re-
nectlon adopts this design for his separating mag
nets He takes slab OF cast-lron lnches
thick l2 inches wide and feet long. cuts a
notch in each end. and then winds his insulated
copper wire on 1t lengthwise. The ordinary bar or
horseshoe magnet attracts only at the end, not
along its side; but by his method OF winding Mr..
Edison makes the whole nine-foot edge OF his slab
a pole" That Is 10 say. 1t VIII possess attractive
power along It's whole length. so long as the wire
carries a current. This rs much the most economi-
cal o. the iron in the OF copper in the coils
and OF curren: that could be made for the partcu-
lar kind OF work done. -Four five such magnets
are mounted all horizontally and one above an
other and the powdered ore fa.s In thin sheet
from a properly arranged trough In front OF the
edges OF the whole set. 1t is said that no less tnan
5D OF these ninefoo magnets are used for the hrst
separation. For the second and third processes
magnets of the same general design are employed;
except that the second set have a width of on'y
about eight inches Instead OF twelve. and the third
Sc, are only four and half inches wide
The stony refuse. or sand. left by this system OF
treating the ore Is sold TO the railway companies
smelling furnace Instead o. shipping 1t thither IN
paste materials that will facilitate smelling. and
shapes it into bricks which are pressed ana are
r. thouli be remarked that Mr. Edlson's method
G, onlv for Certain cass called nagnetic iron
ORES. which are sometimes actually magnetic, nut
various impurities found IN other ores
Even were the new system applied nowhere eise
I'm the country IL promises be a great thing foT
NewJersey The extent OF the iron deposits in this
State not fully known but the great eectrlelan
controls 5000 acres. about fourteen square miles
~, SrIison viii be done by machinery: but there
B. for ell OF
Jess. when the establishment Is In ful Dlast IL IS
probable that in time manuae'nrns nss industries a ,ss
iron produced. At the present time operations nave
been suspended for the winter and both h skei LEA
on The inventors prime object was to perfect the
apparatus. and this has now been asGompshed to
Mr. Edi.,n is said to take great pride In this lat
est achievement. Indeed. he is reported as calm
ing that IL the greatest effort OF his life 80
completely in love Is he win eveby'ms .nat ne q h
who,e thought. time and energy upon 1t. that 1t
cess as the most use; jul OF al his contrbutips 10
civilization II he realizes his own expectations;
no doubt the magnetic separator vii. be source OF
great profit to him and his business associates
Great economies are effected by MS process am
m. surface and 10 A depth OF thirty feet. thus
avoiding the great cost OF sinking deep snatts
Two temporary and parallel railways. about 800
feet apart. made to carry the ends or an I'M
skins" or buckets are lifted from the shallow
excavation between. and deposited on cars ior
TRANSFORMATION to the crushers And, as already IN
timated a good deai Of the apparatus used there
after is automatic. 1t is evident that great deal
Of ore which would be considered worthless. here
and elsewhere. thus he turned to account and
made to pay just the invention of the so.
called ba sic' process permitted the employment OF
non I,essemer ores which had formerly been un-
marketable. .
While Wrestling with the problems involved IN
magnetic separation. Mr.. Edison has gone out 10
the mines every Monday morning and stayed ,hers
until Saturday evening. when he came back to
Llewelyn Park. near West Orange. To spend san
dav with his family. He was Inaccessible 10 the
plhllc and even his charming wife had difficulty
in communicating with him, 40 intense was the
preoccupatlon and absorption of this strange
genius. When possessed with new idea. Mr.. Ed
son is oblivous of everything e.se IN the world.
Even food and sleep negected; and he often
falls TO realize that his most helpful assistants
have physical needs. too. So eager is he to attain
even a minor end when once he sees his way clear.
that he awaits the manufacture OF the necessary
devices breat th.essy, and is not happy until he can
make a test.