carriages there arose another application of
springs which was very prominently before the public during this period,
by means of which it was professed that two drawbacks recognized in the
C and under-spring carriages were obviated, which were caused by the
perch or bar which passes under the body holding the front and hind
parts in rigid connexion, and yet making use of a form of spring to
which the same terms may be applied. These objections are the weight of
the perch, and the limitation which it causes to the facility of
turning, which in narrow roads and crowded thoroughfares is an
inconvenience. The objection to weight is, however, minimized by the
introduction of steel, and as the more advanced builders almost always
construct the perch with a _forked_ arch in front, allowing the wheels
to pass under, the difficulty of a limited lock is in a great measure
overcome (fig. 1). It must be noted, however (and this cannot be too
emphatically stated), that the so-called C springs above referred to are
not at all the same in action as the C spring proper; they are but an
elongation of the ordinary elliptic spring in the form of the letter C
(fig. 2), without adding anything to, but rather lessening their
elasticity, and entirely ignoring the principle of _suspension_ by
leather braces over the C spring proper, by which alone the advantage of
superior ease is to be obtained.

[Illustration: FIG. 2.]

Another improvement which stamps the period under review is the
introduction of indiarubber for the tires of wheels. To produce a
carriage as nearly as possible free from noise and rattle has always
been the aim of high-class coachmaking. A structure composed of wood,
iron and glass, with axle-trees, doors, windows, lamps and other parts,
in use upon the road in all weathers, must from time to time require
some attention with this object. To meet this difficulty, the
introduction of indiarubber has been received by carriage-users as a
great boon. It was about the year 1852 that Mr Reading, who at that time
was known as a builder of invalid carriages, conceived the idea of
encircling wheels with that material, but his method only admitted of
its use on vehicles travelling slowly over good roads. This was improved
upon at a later date by Uriah Scott, who, taking advantage of the
tempering capacity of indiarubber by the chemical action of sulphur,
produced an inner rim of such density as to hold bolts, by which it
could be s