19 
lilKASURIXO MICROSCOPIC OJUECTS— 
1. Eye-piece iiiicTometer. 
2. Stage micrometer. 
3. Photographic method. 
i CLASS BLOWING, 
i 1. The blowpipe. 
2. Pipettes. 
3. Bulbs. 
i 4. Welding. 
5. Sealing and opening gla,sH containers. 
6. Making test tubes. 
I 7. Making perforated tubes f<jr collodiuiii sacks. 
I 
FOLDING PAPER FILTERS. 
PREPARING BACTERIOLOGIC FILTERS (pkixcjples and i>kactue) — 
1. Kaolin. 
2. Diatomaceous earth. 
3. Asbestos. 
4. Sami tiltration. 
I 
I 
i' 
i 
i I 
