414- 
Journal of Agricultural Research 
Vol. XXVII, No. 6 
Table) I. — Grit remaining in the gizzards of fowls at the end of different periods 
Hen No. 
Number of days 
without grit. 
Weight of hen 
at beginning of 
experiment. 
Weight of hen 
when killed. 
Weight of grit 
in gizzard. 
Remarks. 
I. 
14 
Pounds. 
5-2 
Pounds. 
5-4 
Gm. 
9. 5012 
Killed. 
2. 
14 
6.4 
6.3 
13.1136 
Do. 
3 . 
21 
4 * 5 
4.8 
8. 3126 
Do. 
4 . 
21 
5-3 
5-8 
16. 9326 
Do. 
5 . 
28 
4. 6 
4-9 
11. 8763 
Do. 
6. 
28 
7 - 0 
7-3 
22. 6531 
Do. 
7 . 
3<5 
4.8 
5-7 
16. 4389 
Do. 
8. 
36 
2.7 
4. 0 
5 * 0378 
Do. 
9 . 
42 
7.0 
4.2 
8. 4531 
Died of sarcoma. 
10. 
79 
4. 6 
4.7 
6.3700 
Killed. 
11. 
93 
3-6 
3-2 
11. 6341 
Do. 
12. 
120 
3.8 
6. 2 
4 - 9643 
Do. 
*3 . 
124 
5.8 
6. 1 
5 * 6 32 i 
Do. 
14. 
133 
5*6 
4.9 
4 . 5 6 32 
Killed by mites. 
15 . 
134 
7.0 
5*8 
4 . 7532 
Killed. 
16. 
144 
5-7 
5*7 
9. 5920 
Killed by mites. 
17 . 
153 
7 - 1 
5 * 6 
6. 5120 
Do. 
18....! 
154 
6.5 
5*5 
5 - 9633 
Killed. 
19.j 
156 
6.8 
5.8 
14. 0326 
Killed by mites. 
20.j 
170 
(?) 
(?) 
9. 867O 
Died.® 
21. ! 
248 
6. 2 
6. 1 
2. 5200 
Killed. 
22. 
270 
6.3 
6.6 
5. OOOO 
Do. 
23. 
300 
5-7 
5*9 
3 * 9525 
Do. 
24. 
330 
5 -i 
6. 1 
1*9530 
Do. 
25. 
365 
6. 2 
5-2 
2. 5610 
Do. 
26. 
395 
6.7 
7 * 1 
5.8915 
Do. 
“This was a cockerel affected with partial paralysis from which it never entirely recovered. It was 
sent to the laboratory when it weighed about 2 pounds, and remained in the coop until it died, 170 days 
later. 
DISCUSSION 
The feed records show that the appetite of the birds having no ex¬ 
ercise kept up fairly well. 
From the experiments herein recorded it is apparent that a bird may 
go 365 days without grit being fed to it and still have enough remain¬ 
ing in its gizzard to grind its food. The grit that remained in the giz¬ 
zard for 365 days appeared just as sharp as that found at the begin¬ 
ning of the experiment. In fact, the writer does not believe that the 
grinding in the gizzard of the fowl is a sharp-cutting process. Rather 
it appears that the food soaks more or less in the crop, depending on 
the length of time it remains there. It then passes from the crop 
through the second portion of the esophagus to the proventriculus, where 
it lies in an acid secretion. From the proventriculus it passes into the 
gizzard and there the muscles of the walls contract, forcing the soaked 
grain among the particles of grit and by a squeezing rotary motion re¬ 
duces it to fineness. The action is like that of a ball mill. Birds hold 
their weight and remain perfectly healthy on either sharp or dull grit. 
There is a tendency on the part of fowls to eat more grit than is es¬ 
sential for grinding their food. In another series of experiments the 
writer has found that the amount of mineral given off for the first 
twelve days was much greater than that taken in. Further experiments 
showed that this was due to the grit passed off from the gizzard. While 
