1864. | Metallurgy. 533 
like those more modern processes with which they are compared. 
But in every instance where success has attended the recent process, 
it will be found to be due to some original thought, which renders the 
manipulatory details on which that success depends, an original dis- 
covery. Do not let us encourage the habit of endeavouring to 
diminish the small rewards, which, in the aggregate, are gained by 
inventors. In some few cases a substantial recompense for benefits 
gained is bestowed by the public on the originator of a novelty, but in 
by far the larger number, the sole reward is the consciousness that 
success has been deserved, although it has not been achieved. 
There cannot be any difference of opinion, amongst those who are 
acquainted with Metallurgy, on the value of this work, as elucidating 
nearly every point of importance in the processes by which the ores 
are converted into metals. The man of practice may possibly think 
it would have given a more complete character to the work if the 
author had minutely dealt with the numerous phenomena which 
present themselves to the smelter. The man of science may feel that 
he desires on many points, an examination yet more searching than 
that which Dr. Percy has given. To the first we may reply that the 
minuteness desired by him would have detracted from the use of this 
work. It deals sufficiently with all the principal changes, chemical 
or physical, which are essential to the production of marketable metal. 
The minute details if described in a book, cannot be learnt from it, 
and therefore only tend to obscure the more important matters. 
To the latter, we say, for special examinations you must go to 
special treatises, and remember that Dr. Percy has in nearly every 
instance indicated the sources from which he has drawn his facts, and 
from which the additional evidences can be obtained. 
“ Merratturey” is a most valuable contribution to the Literature 
of Science and the Arts. It removes from us the censure that we did 
not possess a treatise on the metals, of any standard character, and it 
gives us a work to which we can with satisfaction refer, as setting 
forth in clear and intelligible language all that itis necessary to know 
of the processes employed in our large works, to give those results 
which have placed us as the first Metal-makers in the world. 
We cannot conclude our notice without speaking of the numerous 
woodcuts which add greatly to the value of the book. In execution 
they are superior to any that can be found in our works on Science. 
The precision with which they have been copied, and the clearness 
with which the minute parts have been engraved, constitute them 
examples to all wood engravers who may have to deal with Mechanics 
or Engineering. The scale which accompanies each engraving adds 
greatly to its value, since this renders it easy to construct a machine 
or build a furnace without any other drawings. 
The author, and all who have aided in the production of this 
work, merit the utmost reward whichan appreciating public can 
bestow on a careful record of the most important of British industries. 
