Works, in Dorset-street, Black-friars, the quantity of coal daily
carbonized amounted to, three chaldron, which afforded a quantity of gas
adequate to the supply of 1,500 Argand lamps; so that twenty-eight
chaldron of coal were daily carbonized at that time, and 76,500 lights
supplied by those two companies only.

At this period the principal object of attention in the manufacture of
gas was its purification. Mr. D. Wilson, of Dublin, took out a patent
for purifying coal gas by means of the chemical action of ammoniacal
gas. Another plan was devised by Mr. Reuben Phillips, of Exeter, who
obtained a patent for the purification of coal gas by the use of dry
lime. Mr. G. Holworthy, in 1818, took out a patent for a method of
purifying it by causing the gas, in a highly-condensed state, to pass
through iron retorts heated to a dark red. For this object and several
others, having in view improvements upon the ordinary method, many other
patents were procured.

OIL gas now appeared in the field as a rival of COAL gas. In 1815, Mr.
John Taylor had obtained a patent for an apparatus for the decomposition
of _oil_ and other animal substances; but the circumstance which
more particularly attracted the public attention to be directed to
_oil_ gas was the erection of the patent apparatus at Apothecary's
Hall, by Messrs. Taylors and Martineau; and the way was prepared for an
application to parliament for the establishment of an Oil Gas Company by
sundry papers in journals, and by the recommendations of Sir William
Congreve, who had been employed by the Secretary of State to inspect the
state of the gas manufactories in the metropolis. This application, made
in the year 1825, proved unfortunate.

In Sir William's Reports is the following account, beginning with the