necessary to meet the objections of the bakers. It is evident, however,
that there must be considerable waste of gas in heating a mass of tiles
and brickwork, such as go to the construction of a common baker's oven,
from the outside; and the objection to handicapping such a costly fuel
as gas in this manner becomes more apparent when it is remembered that
in the usual way the oven is always heated by an internal coal fire.
When it is further considered that the coal commonly used by bakers is
of the most ordinary quality, full of dirt that would condemn it in the
estimation of a gas manager, the sentimental objection to allowing a
purified gas flame to burn in a place which this rubbish is permitted to
fill with foul smoke becomes supremely ridiculous. Consequently, when
Mr. Booer, whose work in connection with the gas muffle is well known
in England and America, seriously addressed himself to construct, upon
altogether new lines, a cheap and practical baker's oven, he wisely put
the gas inside.

There are many other conditions which Mr. Booer, after consultation with
practical bakers and others, set himself to fulfill, the observance
of which lends to the present Blackfriars experiment much of its
interesting character. Thus it was observed that, while it is not
difficult to build an oven in a given spot, and bake bread in it, this
cannot truly be called a _baker's_ oven. By this term must be understood
in particular an oven in an ordinary bakehouse, set in the usual style
and worked by a man with his living to get by it. Before the problem of
extending gas to bakers' ovens could be considered solved, it had to be
attacked from this aspect. Mr. Booer, to do him full credit, seems to
have early appreciated this fact in all its bearings. He not only saw
that it was necessary to save gas, as much as possible, by putting it
inside the oven; but he was told that, in order to meet with any general
success, the cost of converting an oven to the gas system must be