Dairy  Cattle  and  the  Butter  Test. 
53 
Table  II. — Percentage  of  Different  Sizes  of  Fat-corpuscles 
in  Milk  of  Various  Breeds  of  Cows. 
No. 
Breed 
12fi— lOn 
9/x — 
6/1— 4(1 
3/1— 1/1 
1 
Shorthorn 
Per  cent. 
Per  cent. 
1-38 
Per  cent. 
22-39 
Per  cent. 
76-23 
2 
Lincoln  Bed  Shorthorn 
ITl 
5-38 
39-62 
53-85 
3 
Devon  
— 
0-86 
24-03 
75-11 
4 
South  Devon 
— 
0-28 
20-14 
79-.59 
5 
Longhorn  
0-09 
0-85 
33-80 
65-26 
6 
Red  Poll 
— 
1-60 
31-79 
66-61 
7 
Ayrshire 
— 
1-24 
32-75 
66-01 
8 
.1  ersey 
— 
2-61 
32-30 
65-19 
9 
Guernsey 
— 
2-94 
31-18 
65-88 
10 
Kerry 
— 
1-73 
33-66 
64-61 
11 
Dexter 
— 
2-98 
35-58 
61-43 
12 
Gloucester  . , . . . 
— 
1-23 
22-16 
76-61 
13 
Welsh 
— 
0-83 
29-47 
69-74 
The  volume  of  each  size  of  fat-globule,  from  1/x  to  12/i*  in 
diameter  having  been  calculated,  Table  III.  was  computed, 
and  upon  the  figures  so  obtained  all  conclusions  should  be 
based.  Unless  it  is  realised  that  the  rate  of  increase  in  volume 
of  a sphere  as  successive  increments  are  added  to  its  diameter. 
Table  III. — Percentage  of  the  Total  Fat  contained  in  Glohules 
of  each  of  the  different  Sizes  calculated  from  Table  II. 
No. 
Breed 
12/1—10/1 
9/1— 7/1 
6ju. — 4fj. 
3/1— 1/1 
1 
Shorthorn 
Per  cent. 
Per  cent. 
12-73 
Per  cent. 
63-41 
Per  cent. 
23-86 
2 
Lincoln  Red  Shorthorn  . 
16-86 
26-85 
50-12 
6-18 
3 
Devon  
— 
10-35 
64-53 
2.513 
4 
South  Devon 
— 
2-52 
66-36 
31-12 
5 
Longhorn  
1-98 
6-78 
71-84 
19-40 
6 
Red  Poll 
— 
12-89 
69-54 
17-.57 
7 
Ayrshire 
— 
9-86 
74-55 
15-59 
8 
Jersey 
— 
16-63 
71-80 
11-56 
9 
Guernsey  . . ... 
— 
21-11 
63-71 
1.5-18 
10 
Kerry  . . ... 
— 
11-98 
71-99 
16-04 
11 
Dexter 
— 
20-17 
61-71 
15-14 
12 
Gloucester 
— 
12-18 
61-73 
26-10 
13 
Welsh 
8-52 
67-48 
24-00 
is  enormously  great,  deductions  based  on  numerical  expressions 
of  the  quantity  of  fat-globules  in  a sample  of  milk  are  apt  to 
be  misleading.  In  order  to  emphasise  this  point  it  has  been 
’ One  micron  (symbolised  bj^  the  Greek  letter  ju)=one-tbousandtli  of  a 
millimetre,  approximately  1/2.5,000  of  an  inch,  and  is  the  unit  of  length  in 
the  measurement  of  microscopic  objects. 
To  give  some  idea  of  its  size,  a small  pin’s  head  six-hundredths  of  an  inch 
across  would  be  said  to  be  1,500  microns  in  diameter. 
