elpful.

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with many useful and interesting experiments along the lines of modern
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trials and tribulations and final successes are fully discussed.
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a column of "Legal Notes" in which questions of Patent Law, about which
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elucidated.

CURIOSITIES OF SCIENCE AND INVENTION is a department of notes in which
all the curious and ingenious ideas of the day are illustrated and
briefly described.

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The Scientific American Cyclopedia of Formulas

Edited by

ALBERT A. HOPKINS

OCTAVO. 1077 PAGES. 15,000 RECEIPTS Cloth, $5.00. Half Morocco, $6.50.
Postpaid

[Illustration: Book]

This valuable work, which is partly based on the twenty-eighth edition
of "The Scientific American Cyclopedia of Receipts, Notes and Queries,"
contains a collection of about 15,000 selected formulas, covering nearly
every branch of the useful arts and industries. Never before has such a
large collection of valuable formulas, useful to everyone, been offered
to the public.

This work may be regarded as the product of the studies and practical
experience of the ablest chemists and workers in all parts of the world,
the information given being of the highest value, condensed in concise
form, convenient for ready use. Almost every inquiry that can be thought
of relating to formulas used in the various manufacturing industries
will here be found answered.

The formulas are classified and arranged into chapters containing
related subjects, while a complete index, made by professional
librarians, renders it easy to find any formula desired.

Those engaged in any branch of industry will probably find in this
volume m