PROOFS.

We will, whenever desired, furnish tin-type proofs of drawings made by

us, for examination and approval, or correction, before engraving.

A printed proof is sent with each plate when delivered, which may

always be equaled or surpassed in actual work with proper usage.

Scientific American, Vol. XXXVII.—No. 2. [New Series.], July 14, 1877 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures · 第 144 / 213 题