Back Numbers and VolumesIn reply to many interrogatories as to what back numbers and volumes of theScientifio American canbe furnished, we make the following statement,Of Volumes 1, 2 and 3none. Of Volume 4, about 20 Nos., price 50 cts. Of Volume 0, all but four numbers, price, in sheets, $1. Of Volume 6, all; price in sheets, $2; bound, $2,75 Of Vol. 7, &11 ; price in sheets. $2; bound, $2,75. Of Vol. 8, none.