Memorials of the lineage, early life, education and development of the genius of James Watt

JAMES WATT. 237
in the Clyde, or in progress at the various building-yards in 1852,
amounting in all to 73, only 4 were of wood ; while the proportion of
screws to paddle-wheels was as 43 to 30.
Within the last few years Glasgow has entered largely upon the
construction of steam-vessels. From obvious reasons connected with
the narrowness of the channel of the river, the absence of timber
yards, &c, these constructions have been limited to iron. For con-
trary reasons, Greenock, though by no means limited to the erection
of wooden hulls, has continued to be the principal seat of building in
the class of large steamships in wood required for ocean navigation.
During the seven years above specified, accordingly, while Glasgow
and its neighbourhood launched 1 22 iron steamboats, having an aggre-
gate burthen of 70,441 tons, and only one wooden hull of 200 tons, —
Greenock, and Port-Glasgow in its neighbourhood, launched 13 large
wooden steamships of an aggregate burthen of upwards of 18,131 tons,
in addition to 53 of iron, of 29,071 tons. As a specimen of one of the
latter magnificent vessels recently constructed at the iron steamship
building-works of Messrs. Caird & Co. here, — and, at the same time,
as illustrative of the prodigious revolution achieved in this important
art since the appearance in these waters of the little Comet in 1812, —
a draught of the exquisite lines of the Atrato, obligingly furnished by
Mr. James T. Caird of that enterprising firm, is here presented. The
Atrato was contracted for, built, supplied with machinery and other
equipments by the same great establishment, for the West India Royal
Mail Steam Packet Co., on which important line this superb vessel is
altogether unrivalled in speed. The statistical tables of Dr. Strang
illustrate the progress referred to in a very striking manner. From
the year in which the Comet started, down till 1820, only one or two
river steamers were launched every year. In the next five years,
from 1821 till 1825, there were 16 ; from 1826 till 1830, there were
22 ; from 1831 till 1835, there were 41 ; from 1836 till 1840, there