BalILey. | ' Methods of Calculation. Jo 
Some of the analyses reported in this volume are by other 
chemists than those of the Survey, and no definite figures are 
obtainable as to their methods of calculation. Where they have 
represented the hypothetical combination, as is usually the case, 
in terms of grains per gallon, from these figures the grams per 
liter, using the factor 58.31, have been calculated. The radi- 
cals have not usually been calculated in such cases. In several 
analyses the chemists have made no attempt at even a hypo- 
thetical combination, and here only radicals and ions per liter 
are given. 
