I'llOliKMICRiH'.K.II'liy .1X1) II illMCII. M ICKOSCOI'V ll'J 



iluiil>t, OIK' III tilt' must lasciiLitiiiK ami spritaciilar (Ictnniistratiniis 

 within the scope of tfihniral microscopy. A bcakir cont. lining 

 water with a drop or two ol glue or soap, or containing Inn/ol with a 

 few drops of a ruliher solution stirretl into it, or e\en some rather dirty 

 l(M>kini: oil which has seen ser\icc in some machine, ilo not constitute 



I 



rig. 19 — A small photomitrcjgraphic camera (Icvtluiicd li\ tlic writer and used 



extensively in the lalx)rator\' for photographing on film, or on plates. It is ;ised 



when a large numt)cr of small specimens are to be reproduced or when a large field 



is unnecessary. 



interesting exhibits as viewed in the beakers, but placed in suitable 

 cells for ultra-microscopic examination, these licjuids come to life and 

 display the cf)lloidal particles coming into vision as tiny illuminated 

 particles, only to burst into rings of light and pass away into the dark 

 background. The constant irregular motion is the Brownian move- 

 ment and the smaller the particle the more lively it moves. Conglom- 



