Alexandria gazette. [volume] (Alexandria, D.C.) 1834-1974, 1872-11-27
LOCAL. ITEMS.

Gen. HAMPTON 5 LECTURE-Lct every
body, who can, go, to hear Gen. Hampton to-
night. His lecture upon the life and character
of Gen. Lee has been pronounced one Of the
finest intellectual and literary entertainments
ever listened to.
French $ RAILROAD -lMpRov EMENT-
The following is the report otthc Committee Of
the Commercial Exchange upon French Rail
road improvement, the publication of which
in yesterday S GaZette was omitted for want of
room:
That the engine weighs about fifty pounds
and rests upon a truck, and single pair Of driv-
ing wheels, and is worked by spring. In
addition to this there is 4 supplementary pair
of driving wheels, which are used only when
the engine requires more adhesion than is pro-
duced by its weight. In the construction and
application of these wheels consists the inven
ton, the engine without these differing in 20
way from the engine in common use. MIR.
French stated the object of the invention was
to introduce cheaper railroads, and much ight-
er machinery, to be used as feeders to main
lines and in sparsey settled communities where
expensive lines cannot be constructed. He
proceeded to illustrate what he claimed Tor the
invention by a series of experiments.
lst. experiment. The track Is sixteen feet
long laid with small L rails, and there Is at
tached to the engine small car supported on
two trucks, the car weighing - pounds The
spring, which is the motive power OF the en-
CINE, decreases as the engine moves forward,
which makes against u full illustration of the
principle. On the car attached to the engine
100 lbs Of iron were placed and the spring
wound up, the engine only having the adhe
sion due to its weight, as soon as put in motion
the engine slipped its wheels and would not
move forward at all. The supplementary trac-
ton wheels were then brought into use and
the spring again wound up, and the engine ran
over the track readily and easily, drawing the
load Of 100 lbs.
I'd. experiment. The object of this was to
could give it sufficient adhesion to make it
draw the load which the engine had so readily
done simply by the aid Of its traction wheels
10 do this, ore Of the gentlemen present,
weighing about one hundred and twenty-five
pounds, seated himself on the engine and by
his weight so Increased the adhesion OF the en-
CINE, that uuon the spring being again wound
up, the engine moved forward over the track
slowly but drawing the car loaded with the
100 lbs aud without the aid OF the traction
wheels
Sd experiment. The track was then elevated
to grade of 800 feet to the mile, the spring
again wound up, aud an attempt made to make
the engine draw the empty Car up the grade
simply by the adhesion due to its weght-this
it could not do, but slipped its wheels without
advancing at all. Twenty pounds of iron were
then placed upon the car, the spring, again
wound up and the traction wheels brought into
use, and with this load the engine moved IA
pidly up the grade to the end of the track.
4th experiment. Fifty pounds ofiron were
then placed on the engine immediately over
the driving wheels, and the traction wheels re
moved, but this did not give sufficient adhesion
to enable the engine to ascend the grades, for 1t
still slipped its wheels. Then the weight of
the engine was increased until it amounted to
one hundred pounds-this weight was required
to give the engine sufficient adhesion to enable
it to ascend the grade, which 1t could then DO
but moved very slowly. This showed that 1t
required more than twice the weight OF the
engine to be added to it, to produce sufficient
adhesion to enable it to ascend the grade. 1he
weight added being dead weight and unncccs
sary, because better result was effected by the
use of the traction wheels without any addl-
tional weight, the engine moving much more
rapidly. The experiments were conclusive to
show that, by the simple device here used, any
amount of adhesion required can bc produced
without making the engine 50 heavy, and any
grade worked as long as the engine has steam
power sufficient to turn its wheels: When put
in successful operation it must add greatly to
the value of all railroads, to those now construct
ed, as well Us those which shall be hereafter.
(Signcd by Committee Of Commercial TX
change. r. NJ LAWSON
T. b. HooE,
HERBERT BRYANT,
WI. w. HERBERT