Stereotype Printing. 319 



brass disk, turned quite true. Through one of these tubes, which 

 is by much the larger, the syphon passes, and is cemented air tight. 

 The other answers the purpose of the leaden tube described in the 

 preceding article. The brass disk is covered by a piece of gum 

 elastic, which may be obtained by dividing a bag of proper dimen- 

 sions. The covering thus procured, is kept in its place by a brass 

 band or clasp, made to embrace both it, and the circumference of the 

 plate, and to fasten by means of a screw. 



Before applying the caoutchouc, it was softened by soaking it in 

 ether, and a hole, obviously necessary, was made in the centre, by 

 a hollow punch. 



There is no difference between operating with this syphon, and 

 that described in the preceding article, excepting that the juncture 

 of the syphon with the bottle, is effected by pressing the orifice of the 

 latter against the disk covered with gum elastic. 



Art. XIV. — Stereotype Printing. — An original paper of the late 



Zdeut. Gov. Colden, on a new method of printing discovered 



hyhim; together with an original letter from the late Dr. Franklin^ 



on the same subject ; and some account of stereotyping, as now 



practised in Europe, &/-c. by the Editors of the Register. 



We republish from the American Med. and Philos. Register, Vol. 

 I, 1814, p. 439 ; edited by Profrs. Hosack and Francis an inte- 

 resting paper on the origin of Stereotype printing. We are obliged 

 to a friend for pointing out to us this curious document. — Ed, 

 of Am. Jour, of Science, Sfc. 



New Method of Printing. 



" As the art of printing has, without question, been of very great 

 use in advancing learning and knowledge, the abuse of it, as of all 

 other good things, has likewise produced many inconveniences. 

 The number of books printed on the same subject, most of which 

 are nothing but unskilful and erroneous copies of good works, written 

 only for ostentation of learning, or for sordid profit, renders the path 

 to knowledge very intricate and tedious. The reader, who has no 

 guide, and the greatest number have none, is lost in the wilderness of 

 numberless books. He is most commonly led astray by the glaring 



