The principal factor in determining the location of a cheese factory is the available supply of milk. This is usually ascertained by making a canvass, and finding out the number of cows whose milk would be brought to the factory. The quantity of milk or the number of cows necessary to insure sufficient milk for the successful operation of the factory, depends on the variety of cheese to be made. When making types of cheese for which very sweet milk is necessary, the milk must be delivered twice a day. This demand limits the area from which the factory can secure its supply. The length of time the cheeses are held in the curing-room and the work necessary to care for them also limits the area which the factory can serve, because a very large amount of milk cannot be handled when the cheese must be given considerable attention in the curing-rooms. Swiss, Limburger and Brick cheese factories usually do not require a large supply of milk; therefore the factories may be built close together. The size of the Cheddar cheese factories varies but it is generally considered unprofitable to make Cheddar cheese unless there are 5000 pounds of milk available daily. Conditions have changed so that at present different kinds of cheese are made from the surplus milk in market milk plants. In such cases a uniform supply is not absolutely necessary. The climate must also be suitable for the industry. +283. Locating the site.+--In a farming community, several factory sites are usually available. It is best to consider carefully the desirable features of each before trying to make a definite choice. Many of the present cheese factories were located in hollows because it was easy to secure a supply of water, but no thought or attention was given to the disposal of the sewage. The following points should be considered in choosing a site: (1) _Drainage._--A factory should be so located that it has good drainage. Ground that slopes away from the factory makes the disposal of sewage easy. Sewage should not be allowed to run out on the ground and left to decay, thus forming a breeding place for flies, but should run into a cesspool or septic tank.[129] Even in a porous soil, a cesspool frequently clogs and gives trouble. The septic tank seems to be the best method to dispose of the sewage unless the factory is so located that connection can be made with a city sewage system. (2) _Water._--An abundant supply of pure water is essential to a factory. This may come either from deep wells or springs. The value of a never-failing water supply cannot be overestimated.