RELATION OF DAIRYING TO SOIL 179 



LABORATORY PROBLEMS 



XXVII. To Determine the Specific Gravity of the Sulphuric 

 Acid Used 



The specific gravity of sulphuric acid should be 1.82 

 to 1.83. It can be determined as follows: 



a. Carefully weigh a perfectly dry, clean, 10 per 

 cent milk bottle. 



b. Fill the bottle with clean water up to the zero 

 mark and weigh carefully. 



c. Subtracting "a" from "b" will give the weight 

 of the water. 



d. After drying fill the same bottle with sulphuric 

 acid to the zero mark and weigh. 



e. Subtracting "a" from "d" will give the weight 

 of the sulphuric acid. 



f. Dividing the weight of the acid by the weight of 

 the water will give the specific gravity of the sulphuric 

 acid. 



Note: If distilled water is available, it should be used in 

 these determinations. If such water is not available, then 

 good, clean water can be employed. Sensitive scales and accu- 

 rate weights are very essential to obtain accurate results. 



