190 Notice of Parkes’ Essays. 
exact; whereas the figuring of the object in the mind from 
description, is, as respects many of the most useful ideas, 
impossible, and in all very difficult. : 
15. Notice of the Second Edition of Parkes’ Essays. 
Mr. Parkes is well known to the public as an ingenious 
ehemist, and as the author of the ‘* Chemical Catechism,” 
“Chemical Essays,” &c. Of the latter work, he has recent- 
ly published a secondedition. It is not intended as a regu- 
lar system of chemistry, but is merely a collection of es- 
says on different subjects connected with that scicnce, and 
which have not been fully discussed elsewhere. One 
reat design of the author seems to be, to illustrate the 
application of chemical principles to the arts, and to show 
that a knowledge of these principles is essential to the 
proprietors of extensive manufacturing establishments. 
__ That he has succeeded in this design, will be evident to 
all who peruse these Essays. 2 ee 
It would exceed the limits of a notice to consider mi- 
nutely, or individually, the articles which compose these 
volumes, and it might be superfluous to give one article a 
preference to another, since upon this subject there will 
necessarily be a diversity of opinion. 
For in those articles which are more strictly chemical, 
as well as in those which relate particularly to manufac- 
tures, no pains have been spared to collect and arrange 
all important facts concerning them, and the value of the 
work is greatly enhanced, by the numerous practical ob- 
servations and suggestions of the Author. It may not be 
improper to mention, for the information of those who 
are unacquainted with Mr. Parkes as an author, that the 
Essays have been twice reprinted at Paris, and once im 
Germany ; but those who have perused his other writings, 
need only be assured, that the work before us is equall 
interesting, and equally creditable to his industry and 
abilitics. 
This edition is considerably enlarged, is printed in a 
superior style, and adorned with elegant engravings of ap- 
paratus. in short, it may be recommended to the public 
as a valuable collection of facts, useful to the chemist and 
general reader, arranged with great clearness, and treated 
