sept, s, 1923 Determination of Surface Area of Cattle and Swine 427 
Table V .—Surface area as measured and as calculated for swine 
Surface as calculated. 
No. of animal. 
Surface as 
measured. 
S—W* 4 XI/ 6 XK° 
S—W 2 / 3 XK& 
Area. 
Error. 
Area. 
Error. 
13B. 
Sg. cm. 
10,972 
Sg. cm. 
10,860 
Per cent. 
— 1.0 
Sg. cm. 
9,816 
Per cent. 
—10.5 
60B. 
10,625 
ro, 061 
-5*3 
9* 254 
—12.9 
3B . 
14* 759 
14*344 
—2.8 
13*818 
13*708 
-6.4 
14,702 
14,081 
—4*2 
-6.8 
53B. 
16,207 
16,372 
+1.0 
15*605 
-3-7 
12B. 
16,147 
16,053 
-0.6 
15*605 
-3-4 
30S. 
I7>384 
17,625 
+1.4 
16,933 
—2.6 
I7>365 
18,314 
+5-5 
19,009 
+9*5 
40B. 
30B... 
19*330 
19*126 
20,025 
19*401 
+3-6 
+ 1.4 
20,347 
21,148 
+5-3 
+ 10.6 
6*445 
6,270 
—2.6 
5*933 
— 12.0 
2,712 
2,614 
-3-6 
2,272 
—16.2 
2*242 
2,292 
3*936 
+2.2 
1*825 
-18.6 
4,094 
—3-9 
3*678 
— 10.2 
27*215 
26,040 
-4-3 
24* 596 
-9.6 
1*999 
1,898 
—5.0 
1*652 
-17-4 
io6. . .. . 
I* 743 
1* 699 
— 2- 5 
1,431 
— 17.9 
14’850 
15*271 
+2.8 
16,885 
+ 13*7 
16,460 
16,616 
14,666 
+0.9 
18,278 
+ 11.0 
I4>576 
+0.6 
15,396 
+ 5-6 
6 . 
16,528 
16,852 
+2.0 
18,714 
+ I3*» 
8 ... 
15*887 
16,551 
+ 4-2 
17*946 
+ 13*0 
9 . 
17*384 
I7*75i 
+ 2. I 
19,704 
+ 13-3 
14,204 
I4>425 
+1.6 
16,851 
+ 18.6 
«K“i75. &K=*777* 
It will be noted from Tables IV and V that when the surface areas 
were calculated by using the two-thirds power of the weight, the maxi¬ 
mum error with cattle is ± 15.6 per cent and with swine ± 18.6 per cent. 
The constants chosen were 812 for cattle and 777 for swine. The “length- 
weight” formula gives a maximum error of less than ±5.5 per cent with 
either cattle or swine. 
The Meeh formula gives a positive error with the fat animals and a 
negative error with the thin ones. The errors in calculating the surface 
area of cattle by the length-weight formula could not be definitely corre¬ 
lated in any such manner with the condition of the animal. In the case 
of the swine the tendency of the fat animals to give a positive error 
and of the thin animals to give a negative error is quite distinct. We 
are inclined to believe this is due to the fact that as the hogs became 
fatter, the thickening of the subcutaneous fat pushed the root of the tail 
farther back, and so made the length of body measurement too long. 
Whatever the cause may be, we do not consider that difficulty of any 
importance. 
The Moulton formula, which applies only to cattle, gives better results 
than that of Meeh, but is less accurate than the “height-weight” formula. 
Five of the animals, No. 541, 527, 515, 48, and 501, were very fat when 
the surface areas were measured, so according to Moulton the exponent 
5/9 and not 5/8 should be used in these cases. The five have been 
included with the others, but are disregarded when making comparisons. 
The maximum error obtained in the remaining cases is then ±10.2. 
It may be suggested that some of the animals were sufficiently fat so 
that the exponent 5/9 and not 5/8 should be used. This may be true, 
but the usefulness of the formula is diminished if it is necessary to know 
the correct result before deciding which exponent to use. 
