62 PRACTICAL PHOTO-MICROGRAPHY. 



ALKALINE SOLUTIONS. 



Take 1 ounce (chem.) Liquor ammonia f ortiss. and dilute to 10 

 ounces with water. (As soon as any bottle of this solution of 

 ammoniacal gas is opened, an equal bulk of water should be 

 added, or better, water should be added till the hydrometer 

 stands at .920.) In all cases the bottle must be kept closed when 

 not in use, and the stopper of the bottle should be smeared 

 with vaseline. Of course, after this dilution is effected, a 

 double quantity of the solution will be required to represent 

 the quantity given in terms of " liq. amm. fortiss." 



The bottle containing ten ounces (1 oz. ammonia and nine 

 of water) is to be labelled : " liq. amm., 10 per cent. 1 minim= 

 1 minim ammonia." 



Or, 

 Or, 

 Or, 



Sodic Carbonate 1 ounce, avoir 



Water to. . .9 ounces 



Potassic Carbonate 1 ounce, avoir 



Water to 9 ounces 



Sodic Carbonate i ounce, avoir 



Potassic " i ounce " 



Water to 9 ounces 



Label : "Garb. 10 per cent. 10 minims=l grain carb." 



BROMIDE SOLUTION. 



Potassic or ammonic bromide 1 ounce, avoir 



Water to 9 ounces 



Label : " Bromide 10 per cent. 10 minims=l grain bromide." 



CITRATE SOLUTION. 



Sodic or potassic citrate (or half of each) 1 ounce, avoir 



Water to 9 ounces 



Label : " Citrate 10 per cent. 10 minims=l grain citrate." 



(Note : If chemical weights be used, the solutions are to be 

 made up to 10 ounces, and labelled as above.) 



