The Hawaiian gazette., 1868-12-02
The New Road steamer.

great, tlldt euOrts uatt Oceu frequently
made during the past few years to produce
a good and practical traction engine for
this purpose. All these attempts have
been to some extent frustrated by two diff
6culties which, until recently, appeared al
most insuperable. The difficulties con-
sist in the facts, first, that the jar caused
by rough road is so injurious to the ma
chinery and wheels of the engine that they
require continual repair and renewal;
secondly, that if this evil be counterbalanc-
ed by making the locomotive of great
size and weight the injury to the road be-
comes proportionably great, and an OBJ
lection Of a very formidable nature thus
becomes established. Until the beginning
of this year it seemed as though the choice
must lie between carts and horses on the
one hand, and the cost of constant repair
of engines and roads on the other. But
Mr.. Thompson, civil engineer Of Edin-
burgh, has at last succeeded in producing
an engine which, to judge from the sue
cess which has already attended some
very remarkable trials of it, promises a so
luton of the difficulties. MIR. Thompson
had been requested by some friends in the
Island of Java to optain for them road
locomotive for the conveyance Of sugar
from some of the large estates to the port
of Tourabaga
The result of his inquiries after such an
engine was not satisfactory. All those
which he inspected appeared to fail in the
important respects of durability and non
injury TO the roads, The idea then oc-
Cured to him of fitting stout india-rubber
I 70 . ba rhno 80 . tka al khro
to overcome the jar and injury alike to
roads and locomotive. The application
was but the development of principle
which Mr.. Thompson has already applied
to the wheels of the platform trucks at
railway stations with good results. The
preliminary trials of the traction engine
fitted with these tires were eminently sue
cessful. 1t was at once perceived that the
machinery and road became by this simple
device exempt from injury. The steamer,
as Mr.. Thompson calls it, practically runs
along on a self-laid tramway of india-rub-
Der. The Java engine was Of three-horse
power (nominal), but the bite Of the wheels
was so excellent and their smoothness and
ease Of motion were so great that it was
found possible to,take some liberties with
Among other things it was made to cross
a field Of soft grass, to run through field
covered with loose earth to the depth Of
about two feet, to travel over beds Of
broken flint, and to drag huge boiler,
which weighed with its truck nearly thir-
teen tons, up an incline of one in twelve.
These feats were accomplished with the
greatest ease, the locomotive appearing to
float along without any symptom of dis
tress. The trials were continued for sey-
eral weeks with uniform success, and in
the end some other g road steamers were in
course of construction. Two of these have
recently been tried in Edinburgh and Leith,
in presence of large company Of engin-
eers and Others. One Of the engines is in
tended for carrying GOALS in Derbyshire
over nine miles ofroad with inclines Of one
in twelve the other is designed for the
transport of coffee in Ceylon. The former
is of ten-herse power (nominaD, weight
eight tons, and has india-rubber tires IF
teen inches wide and FIVE inches thick. 1t
was built to draw weights Of only fifteen
tons, but the following are among its actual
performances: 1t was run out to colliery
twelve miles from Edinburgh drawing a
train Of four wagons, each weighing tons
10 cwt. At the colliery each wagon re-
ceived load of 514 tons Of coal, SO that
the whole train (including the engine)
weighed forty tons. With this load the
steamer-lOoking like some luggage train
which had escaped from station-traY-
eled with perfect ease along road having
inclines of one in sixteen until it reached
the city There it threaded its way deftly
and surely between the streams Of omni-
staple of the ordinary traffic, and which
were more numerous than usual in conse-
quence Of some games which were going
on, and because it was a Saturday after
noon. The train sped its way satisfacto-
rily over long beds Of broken fints, through
barriers put up for road mending, down
steep streets and round sharp corners, the
train of ninety feet following the engine as
surely and implicitly as the tail Of a serpent
follows its head. In some cases the curves
were SO sharp and close together that the
train assumed the form of letter S. Pass
ing from Junction into bennington road,
the angle was so acute that the train had
to double back upon itself Leith street
has steep and crooked descent, down
which the train passed with ease and f.
nally, the train had TO pass into a very
narrow lane and enter the gates of the
works where it delivered its Goals. The
whole performance was very conclusive
one as far as the tractive powers of the en-
gine and the control Of the train were
concerned. There only remains to notice
the remarkable way in which the india
rubber tires pass over obstacles without
injuriDg them - without even displacing
them, and without injury to themselves.
Thus a potato and carrot which were
purposely laid in the path Of the engine
were passed over uncrushed beds Of loose
fints were undisturbed nor was an in
cision or permanent dent made in the tires
by the sharpest stones. Professor Archer,
in paper which he read upon the stbject
before the British Association, aptly COM
pares these tires to the cushioned feet Of
an elephant or camel, and it is probable
that the tires would prove scarcely more
destructible. The india-rubber tires have
been tried over roads slippery with frost
and ice and wet with complete success.
These engines promise to present soma
important applications. Seeing that they
not only are not destructive TO roads, bat
even independent of them, they may prob
ably be usefully applied for agricultural
purposes. And it Is scarcely necessary to
point out that they may have some impor-
tant military applications. A few Of these
engines working upa the i" Col de Bala-
claya" might have saved many lives in the
Crimean winter nf 1Q5A and tho sncraoaod