Let us now consider the steps necessary in order to arrive at a fair estimate of the labor income. To make the matter concrete, we will assume a farm of 200 acres worth $60 an acre located in central Pennsylvania on a limestone clay loam soil over 1,000 feet above sea level. This farm is to contain 20 acres of timber, a 30-acre apple orchard two years old, 40 acres of pasture, 96 acres of cultivated land divided into six 16-acre fields. The rest of the 200 acres consists of small yards, roadways and waste land. One-half of each of the six 16-acre fields is to consist of a rotation of maize, oats and wheat, each one year, and hay three years, the latter clover and timothy followed by timothy. The other half is to consist of maize, barley, followed by alfalfa four years. In the young orchard there will be grown for a few years potatoes, tomatoes, cabbages and garden peas. After the orchard attains a size which forbids these intertilled crops, a portion of the pasture may be broken up so that these market garden crops may be raised. There will be kept six horses, 20 milch cows, 20 ewes of some mutton breed of sheep, five brood sows and 50 hens. First of all, let attention be called to the broad knowledge of farming required to operate this moderate-sized and comparatively simple farm. The crops to be raised are maize, oats, wheat, clover, alfalfa, timothy, potatoes, tomatoes, cabbages, garden peas and apples. The animal products sold will be chiefly butter fat, wool, mutton, veal, pork and eggs. This is neither a long nor complex list of products. They are all adapted to the farm which the writer has in mind. Yet the man who operates this farm to the highest success will need to have a knowledge of agronomy, or the raising of field crops, of horticulture, animal husbandry, including poultry husbandry and dairying. He needs to have a good understanding of the principles of agricultural chemistry, to have a knowledge of how to prevent and combat fungous diseases and insect enemies. To get the most out of his timber land he should know at least some of the first principles of forestry, and if he has gained some instruction in the study of landscape gardening, his home will be more attractive, and his farm a source of greater pleasure to him. To proceed with the estimate, the first thing to be done is to make a record of the cropping system, giving the areas and the estimated production of each crop. How is the yield per acre to be determined? Clearly, one cannot afford to estimate his profits on the basis of some unusual yields. If one could be assured of 40 bushels of wheat, 60 bushels of oats, five tons of hay, 300 bushels of potatoes, or 200 bushels of apples per acre, or 500 pounds of butter fat per cow, or 150 eggs per hen per year, there would be no difficulty about obtaining a snug labor income. Such results are possible and are appropriate ideals for which to strive, but are not safe as estimates on which to do business.