The steam engine familiarly explained and illustrated; with an historical sketch of its invention and progressive improvement; its applications to navigation and railways; with plain maxims for railway speculators. By the Rev. Dionysius Lardner ... With additions and notes by James Renwick ...

256 THE STEAMI ENGINE.
contrivance; nevertheless, the vessel was successfully worked
in the Thames for 800 miles: she also performed a voyage
from Falinouth to Lisbon, but was prevented from returning
by an accident which occurred to the machinery near the
latter port. In this experimental voyage, the consumption
of fuel is stated never to have exceeded a third of her former
consumption, when worked by Bolton and Watt's engines;
the former consumption of coals being about 800 lbs. per
hour, and the consumption with Mr. Howard's engine being
under 250 lbs. of coke per hour.
After this failure (which, however, was admitted to be
one of accident and not of principle) the government did not
consider itself justified in bestowing further time or incurring greater expense in trying this engine. Mr. Howard,
however, has himself built a new vessel, in which he is
about to place a pair of forty-horse engines. This vessel is
now (December, 1835) nearly ready, and will bring the
question to issue by a fair experiment. The advantages of
the contrivance as enumerated by the patentee are:First, The small space and weight occupied by the machinery, arising from the absence of a boiler.
S'econdly, The diminished consumption of fuel.
Thirdly, The reduced size of the flues.
Fourthly, The removal of the injurious effects arising
from deposite and incrustation.
Fifhly, The absence of smoke.
Some of these improvements, if realized, will be attended
with important advantages in steam navigation. Steamers
of a given tonnage and power will have more disposable
space for lading and fuel, and in short voyages may carry
greater freight, or an increased number of passengers; or
by taking a larger quantity of fuel,* may make greater runs
~ The fuel used in this form of engine is coke, and not coal. A ton of coke
occupies the same space as two tons of coal; the saving of tonnage, therefore,