The method of printing the iractional currency - or notelets, as they ure called - vvili convoy an idea how all j the notes bonds, etc., are to be printed. It is as follows : The " Dötelets" aro printed by a new systein of ntintinfr called the bydrostfttie rnethod, in'vented by S. M. Clark, Esq., and his associate, and the exclusive right to use it has been transferred to the Treasur Department, as well as variooí other inventions by the same parties, free of cost. Fifty are printed on one sheet ; each note is subjected to a pressure of 35 tons making a. total pressure on each plate of 1,750 tons At present thirty-five of these presses are being brougbt into use. A. much largor number wil! ullimately be requircd to print all the bonds, national notes, etc. This kind of " plate printiug" is beautiful, and can, with a magnifving glass, bo very readily diatinSfuished f rom any other; and in this fact alone, the Treasury had a certain tneaiis of deteeting attetnpts to counterieit, for the presses are so massive, (weighing tons each) all worked by a 40 horse power engine, and require so high an order of mechanical talent to keep in order, thflt no cöunterieiter would attempt to procuro or use one.