ROCKY MOUNTAIN MEDICAL ASSOCIATION. 35 
lished the fact that people who Hve wholly or chiefly 
upon a fish diet, as a rule, advance less rapidly, and 
are slower to acquire and apply a knowledge of the 
arts, and also present a noticeably lower grade of in 
telligence than tribes that live by trapping and by the 
chase. None rank so high or advance so rapidly 
in the scale of intelligence as those who derive the 
bulk of their food supply from pastoral and agricultural 
modes of life. Purely hunter tribes have but few if any 
domestic animals, and, strangely enough, the milch- 
cow is among the last added. Only the agricultural 
and village Indians of the present day keep cows. 
The milch-cow, so important to civilized man, was 
no doubt first protected and kept for dairy purposes 
by pastoral and nomadic races of the Old World, and 
is frequently alluded to by the early historians.* 
Savannah, Tenn., and at various places along its course. For descrip- 
tion of them, see Smithsonian Report 1870, page 414. For an account 
of the shell-heaps of California, by Paul Schumacher, see Smithso- 
nian Report 1874, page 335. Shell-heaps in Illinois, near New 
Boston, on the Mississippi, are described in the Smithsonian Re- 
port 1874, page 353. Shell-heaps are also found in many other 
States, as Maine, Massachusetts, Connecticut, Nev^ York, New Jersey, 
Maryland, Virginia, South Carolina, Florida, Alabama, &c. 
* Man had advanced toward civilization and passed out of the lower 
savage state before he commenced to collect and tame what are now 
recognized as domestic animals. These animals were at first kept as 
beasts of burden, or to be slaughtered as required for food. It is 
natural to suppose that certain of them soon attracted attention by the 
amount of milk they were capable of furnishing, and which could be 
utilized as food. The Greeks milked goats and sheep as well as cows. 
History tells us that the milk of the camel, the mare, the ass, and a 
considerable number of other animals has been used as food. A desire 
to increase the food supply no doubt led to the making of cheese, 
which was practiced by pastoral and nomadic races from an early 
period ; but the art of making butter, such as we use, is a compara- 
