Franklin Institute, and especially

Franklin Institute, and especially the Chemical Gazette, which contains
excellent abstracts of foreign papers. The dictionaries resorted to, were
Liebig, Poggendorf, and Wohler's, Ure's Dictionary of Manufactures, Dictionnaire
des Arts, and Dictionnaire de l'lndustrie. In Mineralogy, Dana's admirable
treatise has been freely used, and the author would call attention to
this work, as one of the best works on Mineralogy, not excepting German or
French treatises. Besides this work, Berzelius's Essay on the Blowpipe, and
Rammelsberg's Handworterbuch des Chem. Theils der Mineralogie, have
supplied the applications of Chemistry to this department of natural science.
The sources have been generally too many in the same articles to allow of
space to acknowledge the authority. t
M. H. Boye, M. D., was associated with the author in the first part of the
work, and the subjects from his pen are, Albumen, Alcohol, Alcoholometry,
Analysis, Atmosphere, Balance, Beer, Bile, Blood, Compound Blowpipe, Bone,
Bone-black, Brain, and a few smaller articles, between pages 79 and 372.
Mr. Campbell Morfit was associated with the author in the last half of
the work. The larger articles written by him are, Cochineal, Cotton, Essen
tial Oils, Fats, Gelatin, Madder, Oils, Protein, Quinin, Salicyl, Starch, Stearin,
Sugar, Tartaric Acid, Terpentine, Thermometer, Varnish, Water, Wax, Wheat,
and Wood. Besides these, he penned a large proportion of the smaller articles,
from page 465 to the end.
Professor R. S. McCulloh favored the author with the admirable article
on Electricity, which it is desirable the public should possess in a separate
publication. He also furnished the article Hydrometer.
The remainder of the work is due to the author. That it is not perfect,
he is ready to admit ; nor is it indeed practicable to produce a complete work
on Chemistry, in the present changing state of the science. As an apology
for many imperfections, which the advanced chemist will detect, and for delay
in publication, let it not be forgotten that the work has rather been the production
of leisure hours, amid the unceasing engagements of his profession,
Instruction in Practical Chemistry. The author's own observations and
experience, collected during many years of chemical study and practice, are
interwoven throughout, usually without drawing attention to them. His
principal object has been the dissemination of sound practical knowledge
through the United States, whereby the Chemical Arts, Avhich are most
characteristic of civilized life, may be established and conducted on rational
principles.
James C. Booth.
Philadelphia, February, 1850.