In instituting a comparison between breeds of sheep for _wool-growing_ purposes, it is undeniable that the question is not, what variety will shear the heaviest or even the most valuable fleece, irrespective of the cost of production. Cost of feed and care, and every other expense, must be deducted, in order to fairly test the profits of an animal. If a large sheep consume twice as much food as a small one, and give but once and a-half as much wool, it is obviously more profitable--other things being equal--to keep two of the smaller sheep. The next question, then, is,--_from what breed_--with the same expense in other particulars--_will the verdure of an acre of land produce the greatest value of wool_? And, first, as to the comparative amount of food consumed by the several breeds. There are no satisfactory experiments which show that _breed_, in itself considered, has any particular influence on the quantity of food consumed. It is found, with all varieties, that the consumption is in proportion to the live weight of the grown animal. Of course, this rule is not invariable in its individual application; but its general soundness has been satisfactorily established. Grown sheep take up between two and a half and three and a third per cent. of their weight, in what is equivalent to dry hay, to keep themselves in store condition. The consumption of food, then, being proportioned to the weight, it follows that, if one acre is capable of sustaining three Merinos, weighing one hundred pounds each, it will sustain two Leicesters, weighing one hundred and fifty each, and two and two-fifth South-Downs, weighing one hundred and twenty-five each. Merinos of this weight often shear five pounds per fleece, taking flocks through. The herbage of an acre, then, would give fifteen pounds of Merino wool, twelve of Leicester, and but nine and three-fifths of South-Down--estimating the latter as high as four pounds to the fleece. Even the finest and lightest-fleeced sheep known as Merinos average about four pounds to the fleece; so that the feed of an acre would produce as much of the highest quality of wool sold under the name of Merino as it would of New Leicester, and more than it would of South-Down, while the former would be worth from fifty to one hundred per cent. more per pound than either of the latter.