FORMULAS FOR REAGENTS 399 



Cleaning fluid. — 



Dichromate of potash 20 g. 



Sulphuric acid 30 c.c. 



Water 250 c.c. 



This is excellent for cleaning slides, covers, glassware, developing 

 trays, etc. 



The following need no formulas: acetic acid, hydrochloric acid, 

 nitric acid, sulphuric acid, carbolic acid, hydrofluoric acid, acetone, 

 chloroform, ether, xylol, cedar oil, clove oil, bergamot oil, turpentine, 

 glycerin, paraffin, balsam. 



For photographic formulas see pages 181 to 188. 



