On Rollers, 5 feet by 6 in size. New Edition. Price $5.
This popular work accomplishes for the first time, for Chemistry,
what maps and charts have for geography, geology, and astronomy, by
presenting a new and valuable mode of illustration. Its plan is to
represent chemical composition to the eye by colored diagrams, so that
numerous facts of proportion, structure, and relation, which are the
most difficult in the science, are presented to the mind through the
medium of the eye, and may thus be easily acquired and long retained.
The want of such a chart has long been felt by the thoughtful teacher,
and no other scientific publication that has ever emanated from
the American press has met with the universal favor that has been
accorded to this Chart. In the language of a distinguished chemist,
"Its appearance marks an era in the progress of the popularization of
Chemistry."
It illustrates the nature of elements, compounds, affinity, definite
and multiple proportions, acids, bases, salts, the salt-radical theory,
double decomposition, deoxidation, combustion and illumination,
isomerism, compound radicals, and the composition of the proximate
principles of food. It covers the whole field of Agricultural
Chemistry, and is invaluable as an aid to public lecturers, to teachers
in class-room recitation, and for reference in the family. The mode of
using it is explained in the class-book.
_From the late_ HORACE MANN, _President of Antioch College_.
I think Mr. Youmans is entitled to great credit for the preparation
of his Chart, because its use will not only facilitate acquisition,
but, what is of far greater importance, will increase the exactness
and precision of the student's elementary ideas.
_From_ DR. JOHN W. DRAPER, _Professor of Chemistry in the University of
N. Y._
Mr. Youmans' Chart seems to me well adapted to communicate to
beginners a knowledge of the definite combinations of chemical
substances, and as a preliminary to the use of symbols, to aid
them very much in the recollection of the examples it contains. It
deserves to be introduced into the schools.
_From_ JAMES B. ROGERS, _Professor of Chemistry in the University of
Pennsylvania_.
We cordially subscribe to the opinion of Professor Draper
concerning the value to beginners of Mr. Youmans' Chemical Chart.
JOHN TORREY,
_Professor of Chemistry in the College of Physicians &
Surgeons, N. Y._
WM. H. ELLET,
_Late Professor of Chemistry in Columbia College, S. C._
JAMES B. ROGERS,
_Professor of Chemistry in the University of Pennsylvania._
_From_ BENJAMIN SILLIMAN, LL. D., _Professor of Chemistry in Yale
College_.
I have hastily examined Mr. Youmans' New Chemical Diagrams or Chart
of chemical combinations by the union of the elements in atomic
proportions. The design appears to be an excellent one.
History of Philosophy.
A History of Philosophy: