ystem of sinking shafts for mines and wells, invented by
Kind and Chaudron, exhibited here as in Philadelphia, attracts great
attention from its gigantic proportions. Imagine an immense
boring-chisel (_trepan_), weighing 26,000 pounds and with a breadth of
over six feet, worked up and down by machinery, the steel studs on its
face stamping the rocks into dust, so that they can be removed with a
bucket with bottom valves which is dropped into the hole and is worked
up and down until the detritus and water, if any, creep into it, when it
is withdrawn and emptied. The repetition of these processes makes the
shaft of two metres diameter. Then comes the larger trepan, with a width
of 4.80 metres, and repeats the process on a larger scale. This enormous
chisel weighs 44,000 pounds. The system is much in favor, and forty-five
shafts have been thus sunk between 1854 and 1877 in Belgium, France,
England and Germany. Cast-iron lining is lowered in sections as the
shaft deepens, the sections being added at the top and bolted together.

The Belgian exhibit contains also one of those immense paper-machines
invented by the brothers Fourdrinier about fifty years ago, and now used
almost universally for the best class of machine-made papers. They are
used by Wilcox at Glen Falls, Delaware county, Penn., in making the
government note and bond paper, and are a marvel of art. The Frenchmen
who invented the machine brought it into use in England, but they were
much hampered and discouraged by difficulties, and it was never a
pecuniary success to them. It was a legacy to the future, and they have
joined the army of martyrs to mechanical science. The machine in the
Belgian section is one hundred and thirty feet long, and the Swiss
machine, near by, is nearly as large. The French, with their customary
ingenuity, have reduced the proportions very considerably. The Swiss
machine makes paper one metre and a half wide.

The remainder of the Belgian exhibit of machinery may be summarized:
rock drills on the principle of those used at Mont Cenis; the
gas-engines of Otto; machine tools, lathes, drills and planers; a very
curious machine for cutting bevel or straight gears, built by a firm at
Liege, and worthy of attention by Mr. Sellers or Mr. Corliss, whose
ingenious machines for the same purpose were at Philadelphia; the
woollen machinery of Celestine Martin of Verviers, which I recollect to
have seen in Philadelphia also; multitubular boilers, ru