324 HOW TO SEE WITH THE MICROSCOPE. 



being" completed, pour the whole into a thousand grain 

 bottle, rinse two or three times with distilled water, 

 adding this to the measuring bottle, and finally add dis- 

 tilled water to make the whole to 1,000 grains. Let it 

 stand for a few hours, after which time should there 

 form a precipitate of the basic salt, add two or three 

 drops more of the- acid. The solution may now be 

 transferred to the regular bottle for use. Two hun- 

 dred grains of this standard solution are (should be) 

 equivalent to one grain of urea. 



Baryta Solution. In one bottle make a cold solution 

 saturated with nitrate of baryta; four ounces of dis- 

 tilled water will be sufficient. In another bottle satu- 

 rate eight ounces of distilled water (cold) with caustic 

 baryta. When the solutions are fully saturated, which 

 may be known by the baryta remaining in excess in the 

 tw T o bottles, allow a little time for the two solutions to 

 become clear; then carefully decant as much as possible 

 of the nitrate solution into your regular bottle, and to 

 this add twice the volume of the caustic solution, the 

 two combined forming the baryta solution for use in 

 analysis. 



Carbonate of Soda Paper. In a bottle prepare a 

 saturated solution of carbonate of soda. When fully 

 saturated pour into a large dish or platter, provide 

 sheets of ordinary printing paper, saturate these and 

 suspend the sheets until quite dry; cut into strips one 

 inch wide by six or seven inches long-, and preserve in a 

 wide mouthed bottle fitted with a well-fitting stopper. 



Measuring Bottle. Procure one of the long and slim 



