126 ON THE PLEACESOPSFISTH Li 
AN EASY WAY TO CALCULATE THE NUMBER OF GRAINS OF 
NITROGEN PRESENT IN DIFFERENT WEIGHTS OF NITRO- 
GENOUS COMPOUNDS. 
Though fractions of a grain are important in a chemical 
analysis it is near enough in practical dieting to be within 
3 ofan ounce. The daily range of nitrogenous compounds 
taken is between 4 and 54 ounces. 
Calculate 438 gr. to 0z.; 219 to 4 02.3 110 to 4 oz, (near 
enough). For ready reference—expressed in grains— 
A 02,'= 2752 or. ; 44 OZ. = 1862 or. > 44 07, = 197 mare 
42 OZ. = 2081 gr.; 5 OZ. = 2190 gr.; 54 Oz. = 2300 gr; 
54 0Z. = 2409 gr. (more exact than 2410). 
If the analyses of various nitrogen compounds is ex- 
amined it will be seen that about 154 or 16 parts per 
hundred (three examples of which are given on p. 27) 
are nitrogen. This is so uniformly the case in all analyses 
that for the convenience of calculation wthout analysis 
16 parts in the hundred of any nitrogenous compound are 
taken as nitrogen. In making calculations in grains every 
Ioo grains of a nitrogenous compound is taken to contain 
16 grains of nitrogen, every 50 contains 8, every 25 con- 
tains 4, and so on. 
Beginning at the 4 oz., that is 1752 grains, there are 17 
hundreds (17 times 16= 272) and one fifty (= 8 grains N), 
and the odd 2 may be omitted ; so 1752 grains of nitrogen 
compound contain 272 + 8 = 280 grains of nitrogen. 
Working out this way or any other more convenient, the 
results come :— 
Nitrogenous 
Grains of 
compound. Nitrogen. 
OZ. 
4 orexpressed in grains . 1752contain . , 280 
4} ue o .) MB62 aaa . . 298 
4} > 5 5 tae ms OLE 
4} 55 5 ; 2OSiaa., . . 38383 
5 - 56 = 21900 Vip ooU 
5h 35 = 2 23007. . . 368 
54 3 s - 2409 ',, oY Ge (O88 
This can, of course, be worked the reverse way. Suppos- 
ing a diet is wanted to contain 350 grains of nitrogen, then 
5 ounces of some nitrogen compound must be taken. 
