Mr. Harley--whose admirable dairy establishment was erected for the purpose of supplying the city of Glasgow with a good quality of milk, and which has contributed more than any thing else to improve the quality of the milk furnished to all the principal cities of Great Britain--adopted the following system of feeding with the greatest profit: In the early part of the summer, young grass and green barley, the first cutting especially, mixed with a large proportion of old hay or straw, and a good quantity of salt to prevent swelling, were used. As summer advanced, less hay and straw were given, and as the grass approached ripeness, they were discontinued altogether; but young and wet clover was never given without an admixture of dry provender. When grass became scarce, young turnips and turnip leaves were steamed with hay, and formed a good substitute. As grass decreased, the turnips were increased, and at length became a complete substitute. As the season advanced, a large proportion of distillers' grains and wash was given with other food, but these were found to have a tendency to make the cattle grain-sick; and if this feeding were long-continued, the health of the cows became affected. Boiled linseed and short-cut wheat straw mixed with the grains, were found to prevent the cows from turning sick. As spring approached, Swedish turnips, when cheap, were substituted for yellow turnips. These two roots, steamed with hay and other mixtures, afforded safe food till grass was again in season. When any of the cows were surfeited, the food was withheld till the appetite returned, when a small quantity was given, and increased gradually to the full allowance. But the most elaborate and valuable experiments in the feeding and management of milch cows, are those made, not long since, by Mr. T. Horsfall, of England, and published in the Journal of the Royal Agricultural Society. His practice, though adapted more especially, perhaps, to his own section, is nevertheless of such general application and importance as to be worthy of attention. By his course of treatment he found that he could produce as much and as rich butter in winter as in summer.