in the same time,multiply the diameter of the driver by its number of revolutions, anddivide the product by the number of revolutions of the driven pulley.The product will be its diameter. To ascertain the size of a driver,multiply the diameter of the driven pulley by the number of revolu-tions you… … CORRESPONDENCE. To the Editor of tlie Journal o/ Domestic A2Jj>Kances and SewingMaclmie Gazette.Sib,—How conld I obtain each month the return of Imports fromJanuary to end of August, and from March to end of August, asyour journal does not give some months—May, for instance. Tours truly, A. B.…