One of the ways in which the value of tamed beasts would be soon appreciated would be that of giving milk to children.  It is marvellous how soon goats find out children and tempt them to suckle.  I have had the milk of my goats, when encamping for the night in African travels, drained dry by small black children, who had not the strength to do more than crawl about, but nevertheless came to some secret understanding with the goats and fed themselves.  The records of many nations have legends like that of Romulus and Remus, who are stated to have been suckled by wild beasts.  These are surprisingly confirmed by General Sleeman’s narrative of six cases where children were nurtured for many years by wolves in Oude. (Journey through Oude in 1849-50, i. 206.)

Breeding freely.—­Domestic animals must breed freely under confinement.  This necessity limits very narrowly the number of species which might otherwise have been domesticated.  It is one of the most important of all the conditions that have to be satisfied.  The North American turkey, reared from the eggs of the wild bird, is stated to be unknown in the third generation, in captivity.  Our turkey comes from Mexico, and was abundantly domesticated by the ancient Mexicans.

The Indians of the Upper Amazon took turtle and placed them in lagoons for use in seasons of scarcity.  The Spaniards who first saw them called these turtle “Indian cattle.”  They would certainly have become domesticated like cattle, if they had been able to breed in captivity.

Easy to tend.—­They must be tended easily.  When animals reared in the house are suffered to run about in the companionship of others like themselves, they naturally revert to much of their original wildness.  It is therefore essential to domestication that they should possess some quality by which large numbers of them may be controlled by a few herdsmen.  The instinct of gregariousness is such a quality.  The herdsman of a vast troop of oxen grazing in a forest, so long as he is able to see one of them, knows pretty surely that they are all within reach.  If oxen are frightened and gallop off, they do not scatter, but remain in a single body.  When animals are not gregarious, they are to the herdsman like a falling necklace of beads whose string is broken, or as a handful of water escaping between the fingers.

The cat is the only non-gregarious domestic animal.  It is retained by its extraordinary adhesion to the comforts of the house in which it is reared.

An animal may be perfectly fitted to be a domestic animal, and be peculiarly easy to tend in a general way, and yet the circumstances in which the savages are living may make it too troublesome for them to maintain a breed.  The following account, taken from Mr. Scott Nind’s paper on the Natives of King George’s Sound in Australia, and printed in the first volume of the Journal of the Geographical Society, is particularly to the point.  He says:—­