HAMMEL.
Flexible, quarto, 42 pages.

Illustrated 30 cents A pupil's laboratory manual and notebook for the first term's work.
Blanks are left in which the pupil writes his observations and the principles illustrated.
_Copies of any of these books will be sent, prepaid, to any address on receipt of the price by the Publishers:_ American Book Company NEW YORK.

CINCINNATI.

CHICAGO * * * * * Laboratory Physics Hammel's Observation Blanks in Physics By WILLIAM C.A.HAMMEL, Professor of Physics in Maryland State School, Boards, Quarto, 42 pages.

Illustrated 30 cents These Observation Blanks are designed for use as a Pupil's Laboratory Manual and Note Book for the first term's work in the study of Physics.
They combine in convenient form descriptions and illustrations of the apparatus required for making experiments in Physics, with special reference to the elements of Air, Liquids, and Heat; directions for making the required apparatus from simple inexpensive materials, and for performing the experiments, etc.