850
revolutions per minute, and develops 12 horse power when driving the
screw at 280 revolutions. Current is supplied by a new type of
accumulators made by Messrs. Commelin & Desmazures. One hundred and
thirty two of these accumulators are fitted in the bottom of the boat,
the total weight being about 2 tons.

In ordering this boat the French government stipulated a speed of 6
knots to be maintained during three hours with an expenditure of 10
horse power. The result of the trials gave a speed of 61/2 knots during
five hours with 12 horse power, and sufficient charge was left in the
accumulators to allow the boat to travel on the following day for four
hours. This performance is exceedingly good, since it shows that one
horse power hour has been obtained with less than 60 lb. of total
weight of battery.

* * * * *

THE COMMERCIAL EXCHANGE, PARIS.

Leveling the ground, pulling down old buildings, and distributing
light and air through her wide streets, Paris is slowly and
continuously pursuing her transformation. At this moment it is an
entire district, and not one of the least curious ones, that is
disappearing, leaving no other trace of its existence than the
circular walls that once inclosed the wheat market.

It is this building that, metamorphosed, is to become the Commercial
Exchange that has been so earnestly demanded since 1880 by the
commerce of Paris. The question, which was simple in the first place,
and consisted in the conversion of the wheat market into a commercial
exchange, became complicated by a project of enlarging the markets. It
therefore became necessary to take possession, on the one hand, of
sixty seven estates, of a total area of 116,715 square feet, to clear
the exchange, and, on the other, of 49,965 square feet to clear the
central markets. In other words, out of $5,000,000 voted by the common
council for this work, $2,800,000 are devoted to the dispossessions
necessitated by the new exchange, $1,800,000 to those necessitated by
the markets, and $400,000 are appropriated to the wheat market.

The work of demolition began last spring, and the odd number side of
Orleans street, Deux-Ecus street, from this latter to J.J. Rousseau
street, Babille street, Mercier street, and Sortine street, now no
longer exist. All this part is to-day but a desert, in whose center
stands the iron trussing of the wheat market cupola. It is on these
grounds that will be