Scientific American Supplement, No. 312, December 24, 1881 | Page 4

140 car cleaners, 40 lamp
men, and 470 blacksmiths, boiler makers, and other mechanics
employed on the structure and in the shops. Most of the ticket agents
are telegraph operators, but there are 13 other operators employed.
There are four double-track lines in operation. The aggregate daily
receipts vary from $14,000 to $18,000; and as many as 274,023
passengers have been carried in one day. Engineers are paid from $3 to
$3.50 per day; ticket agents, $1.75 to $2.25; conductors, $1.90 to $2.50;
firemen, $1.90 to $2; guards or brakemen, $1.50 to $1.65; and gatemen,
$1.20 to $1.50. The above items do not include machinists and other
employés in the workshops, or the general officers, clerks, etc.
* * * * *

AMERICAN ANTIMONY.
A Baltimore dispatch informs us that a carload of antimony, ten tons in
all, was lately received by C.L. Oudesluys & Co., from the southern
part of Utah Territory, being the first antimony received in the East
from the mines of that section. The antimony was mined about 140
miles from Salt Lake City. The ore is a sulphide, bluish gray in color,
and yields from 60 to 65 per cent. of antimony. All antimony heretofore
came from Great Britain and the island of Borneo, and paid an import
duty of 10 per cent. ad valorem, and there is also some from Sonora. It
is believed that with proper rail facilities to the mines of the West there
will be no need of importations.
* * * * *

SOME OF THE DEVELOPMENTS OF MECHANICAL
ENGINEERING DURING THE LAST HALF-CENTURY.[1]
[Footnote 1: Paper read in Section G (Mechanical) of the British
Association.]
By SIR FREDERICK BRAMWELL, V.P. Inst. C.E., F.R.S., Chairman
of the Council of the Society of Arts.
I am quite sure the section will agree with me in thinking it was very
fortunate for us, and for science generally, that our president refrained
from occupying the time of the section by a retrospect, and devoted
himself, in that lucid and clear address with which he favored us, to the
consideration of certain scientific matters connected with engineering,
and to the foreshadowing of the directions in which he believes it
possible that further improvements may be sought for. But I think it is
desirable that some one should give to this section a record, even
although it must be but a brief and an imperfect one, of certain of the
improvements that have been made, and of some of the progress that
has taken place, during the last fifty years, in the practical application
of mechanical science, with which science and its applications our

section is particularly connected. I regret to say that, like most of the
gentlemen who sat on this platform yesterday, who, I think, were,
without exception, past presidents of the section, I am old enough to
give this record from personal experience. Fifty years ago I had not the
honor of being a member, nor should I, it is true, have been eligible for
membership of the association; but I was at that time vigorously
making models of steam-engines, to the great annoyance of the
household in which I lived, and was looking forward to the day when I
should be old enough to be apprenticed to an engineer. Without further
preface, I will briefly allude to some of the principal developments of a
few of the branches of engineering. I am well aware that many
branches will be left unnoticed; but I trust that the omissions I may
make will be remedied by those present who may speak upon the
subject after me.
I will begin by alluding to
THE STEAM-ENGINE EMPLOYED FOR MANUFACTURING
PURPOSES.
In 1831, the steam-engine for these purposes was commonly the
condensing beam engine, and was supplied with steam from boilers,
known, from their shape, as wagon boilers; this shape appears to have
been chosen rather for the convenience of the sweeps, who periodically
went through the flues to remove the soot consequent on the imperfect
combustion, than for the purpose of withstanding any internal pressure
of steam. The necessary consequence was, that the manufacturing
engines of those days were compelled to work with steam of from only
3½ lb. to 5 lb. per square inch of pressure above atmosphere. The
piston speed rarely exceeded 250 feet per minute, and as a result of the
feeble pressure, and of the low rate of speed, very large cylinders
indeed were needed relatively to the power obtained. The consumption
of fuel was heavy, being commonly from 7 lb. to 10 lb. per gross
indicated horsepower per hour. The governing of the engine was done
by pendulum governors, revolving slowly, and not calculated to exert
any greater effort than that of raising the balls at the end of the
pendulum