e plant had already been liberally provided.

Briefly described, the process consisted in mixing the concentrates with
the special binding material in machines of an entirely new type, and in
passing the resultant pasty mass into the briquetting machines, where it
was pressed into cylindrical cakes three inches in diameter and one and
a half inches thick, under successive pressures of 7800, 14,000, and
60,000 pounds. Each machine made these briquettes at the rate of sixty
per minute, and dropped them into bucket conveyors by which they were
carried into drying furnaces, through which they made five loops, and
were then delivered to cross-conveyors which carried them into the
stock-house. At the end of this process the briquettes were so hard
that they would not break or crumble in loading on the cars or in
transportation by rail, while they were so porous as to be capable of
absorbing 26 per cent. of their own volume in alcohol, but repelling
water absolutely--perfect "old soaks."

Thus, with never-failing persistence and patience, coupled with intense
thought and hard work, Edison met and conquered, one by one, the complex
difficulties that confronted him. He succeeded in what he had set out
to do, and it is now to be noted that the product he had striven so
sedulously to obtain was a highly commercial one, for not only did the
briquettes of concentrated ore fulfil the purpose of their creation, but
in use actually tended to increase the working capacity of the furnace,
as the following test, quoted from the Iron Age, October 28, 1897,
will attest: "The only trial of any magnitude of the briquettes in
the blast-furnace was carried through early this year at the Crane Iron
Works, Catasauqua, Pennsylvania, by Leonard Peckitt.

"The furnace at which the test was made produces from one hundred to one
hundred and ten tons per day when running on the ordinary mixture. The
charging of briquettes was begun with a percentage of 25 per cent.,
and was carried up to 100 per cent. The following is the record of the
results:

RESULTS OF WORKING BRIQUETTES AT THE CRANE FURNACE

Quantity of Phos- ManDate
Briquette Tons Silica phorus Sulphur ganese
Working
Per Cent.
January 5th 25 104 2.770 0.830 0.018 0.500
January 6th 37 1/2 4 1/2 2.620 0 740 0.018 0.350
J