Dodgeville chronicle. [volume] (Dodgeville, Wis.) 1862-current, 1868-11-27
ThompsOn's Road Steamer.

ThompsOn's Road Steamer. 81
The following description of the new
steam wagon for common roads was given
in paper read before the British Associ-
alton by Prof. Archer. 1t contains more
complete description than those which
have appeared hitherto, and all informa-
ton concerning an invention which prom
ises to be of especial value on the prairies
of the Northwest, will be interesting:
This road steamer has wheels made of
material which at first sight does not
look very likely substance to stand the
heavy work they are subjected to- The
tyres are made of bands Of vulcanized
india-rubber, about 10 in. wide and in.
thick Incredible as it may appear, this
soft and elastic substance not only carries
the great weight of the road steamer with
out injury, but they pass over newly
broken road metal, broken f1ints, and all
kinds of sharp things, without even leav-
ing a mark on the india-rubber They do
not sink into the road in the least degree.
They pass over stones lying on the surface
without crushing them. Those soft and
elastic tyres resemble in some degree the
feet of an elephant. Both the camel and
the elephant have very large soft cushions
instead of hard hoofs, and no other ami
NAL can stand so much walking over hard
roads as they can accomplish.
The power required to propel the road
steamer is very much less than what would
be required if the tyres were hard and
rigid They do not crush nor sink into
the roadway. The machine, as it were,
floats along on the india-rubber. and all The
power used in crushing and grinding the
stones under rigid tyres is entirely saved.
It might at first sight be supposed that it
would take great deal of power to pro-
pei heavy carriage On soft tyres; but if
the tyres are elastic as well as soft, the
power used in COMPRISING the tyre in
front of the wheel is nearly all given back
as the elastic tyre expands behind the
wheel.
The india-rubber tyres require scarcely
any more power to propel them over soft
bad roads or over loose gravel roads than
on the best paved streets. The reason OF
this is quite obvious; they do not sink into
roads, and do not grind down the stones in
the least degree.
Trials have been made It Leith by run
ming the road steamer across soft grass
field, in which an ordinary steam carriage
would certainly have sunk. The way it
ran through the grass without even leav-
ing track, was very remarkable; but
when it made for part of the field which
had Just been covered with loose earth to
the depth of it. or it,, and ran straight
across, the surprise Of those present was
great indeed. The weight of the road
steamer is between four or five tons; and
yet the wheels in passing over the loose
earth compressed it so little that walk
ing stick could easily be pushed down in
the track of the wheels without any exer-
ton. 1t is quite clear that one of the
great difficulties farmers had to contend
with in using steam engines in ploughing
is now removed, for the road steamer will
run through any field, even when newly
ploughed, without any difficulty. After
various evolutions, showing the ability of
the road steamer to run about where there
were no roads, it passed out into the street,
and, taking large omnibus full OF pas
sengers in tow, it proceeded up the Bon
| nington road to Messrs. Gibson & Walk
er's mills, where it took a large wagon,
| weighing, with its load of flour, about ten
tons, up steep lane full of
| holes and ruts, and rising with a
gradient of one in twenty. 1t was
obvious that the road steamer was able to
do great deal more than it had to do in
this trial. The bite on the road is some
thing marvellous, and the easy way in
which it floated along on its soft and elias
tic tyres was very curious. When riding
on the road steamer the feeling is like
what would be experienced in driving
over a smooth, soft grass lawn. There is
absolutely no Earring at ALL Thus the
machinery is spared the severe trials arts
ing from the blows ard jolts to which it
is subjected when mounted on common
wheels. There is, Incredible as it may
appear, no appearance of wear on the in
dia-rubber tyres. The original surface
which the rubber had when it left the
mandatory is still visible. .a,r b
The steamer which was the subject Of
the experiments he'd another speciality be-
sides the wheels. 1t was fitted with YER
tical boiler, which is one of the most eco
nomical steam. generators yet produced.
Externally the boiler looks very much
like others of vertical construction; but
internally it is entirely different. A glance
at a sectional drawing of it will make its
advantages apparent to practical men.
Its powers may be illustrated by giving
the result of series of trials made in
contrast with a common locomotive boiler,
and an upright boiler of the ordinary kind.
The latter evaporated 1856 ID Of water for
each pound of inferior Scotch coal
burned; the locomotive boiler 413 lb. of
water for each pound of coal; and the
new boiler 4.68 Id. of water for like ex-
penditure of fuel. In contrasting the
heating surface the new boiler had a still
greater superiority. With So it. of heating
surface it evaporated 1914 cubic feet Of
water per hour. The common vertical
boiler, with ~ #. of surface, evaporated
IA cubic feet of water per hour and the
locomotive boiler with 1877 #. of heating
surface, evaporated Is #. of water per
hour. This shows the new boiler to pos
sess very decided advantage.
The tractive powers of the machine
have surpassed all expectation. 1t was
constructed to drag an omnibus, weighing,
with its load of (say) thirty passengers,
about four tons on level ROAD, but its
powers are so greatly in excess of this
task, that no load yet placed behind it has
fully tested its power. An opportunity
was offered which was confidently ex-
pected would show the limits Of its capa-
bilities. A huge steam boiler, weighing
with It's truck between twelve and thir-
teen tons, had to be dragged up hill
rising one In twelve. The little road
steamer was chained to the truck, and
steadily drew the great boiler to the top of
the hill, the india-rubber wheels biting
the ground in the most perfect manner:
there was not the least sign of slipping.
The boiler was drawn from the works
of Messrs. Hawthorne g Co., along the
Junction road, and then up the biIlv Rom