The Scientific American Supplement is a distinct paper from the Scientific American. THE SUPPLEMENT is issued weekly. Every number contains 16 octavo pages, with handsome cover, uniform in size with Scientific American. Terms of subscription for Supplement, $5.00 a year, postage paid, to subscribers. Single copies 10 cents. Sold by all news dealers throughout the country.

Combined Rates.- The Scientific American and Supplement will be sent for one year, postage free, on receipt ofseven dollars. Both papers to one address or different addresses, as desired.

The safest way to remit is by draft, postal order, or registered letter.

Address MUNN & CO., 37 Park Row, N. Y.