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. --> Single copies of any desired number of the SUPPLEMENT sent to any address on receipt of 10 cents. * * * * * CARRYING PEACE INTO AFRICA. To carry war into Africa has been a proverb ever since Rome vowed the destruction of Carthage. But the Carthagenian invasion was a modern episode in Africa's experiences of that nature. On one of the earlier monuments of Egypt there is figured a slave-hunter's raid upon an Ethiopian village, the horrid details of which are said by travelers to be an accurate picture of a slave raid of to-day. The same murderous work has been going on incessantly for at least 4,000 years: how much longer there is no telling. For all these ages the African borders have known war and war only, and of the most destructive and barbarizing nature. Recently, under the influence of Sir Samuel Baker, Colonel Gordon, and the civilized world in general, the Khedive of Egypt has carried war into the interior in the interests of peace: a conquest in a measure justified by the suppression of inter-tribal war for the filling of slave pens, and the abolition of the slave trade down the Nile. A similar reform has been effected on the east coast by the pressure of English power on the Sultan of Zanzibar. And the immediate effect of these two movements has been to prevent the butchery or enslavement of not less than half a million negroes annually.