TERMS:--SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, _five dollars_. One copy of SCIENTIFIC AMERICAN and one copy of SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, _seven dollars_. CLUBS.--One extra copy of the SUPPLEMENT will be supplied gratis for every club of five SUPPLEMENT subscribers at $5.00 each. All the back numbers of the SUPPLEMENT, from the commencement, January 1, 1876, can be had. Price 10 cents each. NOW READY.--The SCIENTIFIC AMERICAN SUPPLEMENT for 1876. Complete in two large volumes. Over 800 quarto pages; over 2,000 engravings. Embracing History of the Centennial Exhibition. New Illustrated Instructions in Mechanical Drawing. Many valuable papers, etc. Price five dollars for the two volumes, stitched in paper; or six dollars and fifty cents, handsomely bound in stiff covers. Remit by postal order. Address MUNN & CO., PUBLISHERS, 37 Park Row, New York. [Hand->] Single copies of any desired number of the SUPPLEMENT sent to any address on receipt of 10 cents. * * * * * PUBLISHERS' NOTICE. New subscriptions to the SCIENTIFIC AMERICAN and the SCIENTIFIC AMERICAN SUPPLEMENT will, for the present, be entered upon our books to commence with the year, and the back numbers will be sent to each new subscriber unless a request to the contrary accompanies the order. Instead of a notice being printed on the wrapper, announcing that a subscription is about to end, the time of expiration is now denoted in the printed address each week, so that the subscriber may see when the period for which he has prepaid is about to expire. * * * * * DATES AND THE DATE PALM.