LANTERN SLIDES WITHOUT A NEGATIVE. 



VV. G. Tight. 



As improved methods of teaching are being constantly developed 

 and the instructor is anxious to avail himself of them, there seems to 

 be a growing demand for the stereoptican. In fact the time has al- 

 ready arrived when the class-room is not complete unless there is pres- 

 ent some good instrument for projection. And there is no depart- 

 ment of instruction in which it cannot be used to advantage. Its 

 value lies m the fact that a large number of individuals may view the 

 representation of the same object during its explanation. There are 

 a number of large firms who make it a business to prepare slides for 

 class-room and lecture work. But the instructor who depends wholly 

 upon these to supply the needed slides has yet to learn to what mani- 

 fold uses his instrument can be put. One can not buy what is de- 

 sired. One must learn to make for himself. As the requirements of 

 every teacher are different and each one laboring alone as it were 

 often hits upon little methods that might be useful to others working 

 in different lines, it is my intention to give a few of my various meth- 

 ods for the manufacture of my own slides, trusting there may be a 

 few points of value to some one. It is my purpose to speak only of 

 those methods in which no negative is required for the preparation of 

 the slide, and first of those methods in which not even a camera or 

 but little knowledge of photographic manipulation is required. 



Next to the use of a blackboard and free hand drawing for rep- 

 resentation comes the preparation of a slide for the lantern by draw- 

 ing on glass. The glass must first be prepared and under this head 

 might be mentioned two ways : 



First, flow the glass with a solution of collodian, or a negative 

 varnish and when dry, write or draw with a fine pen and india ink. 

 This gives the desired object in black against a white ground. 



The second way gives a light drawing against a dark ground and 

 this may be accomplished by smoking the glass over burning camphor 

 and drawing the design with a needle point. To make this perma- 

 nent, flow with collodian or a negative varnish. Always preserve all 



