The second and the third assistant managers are the heads of non-selling organizations within the store, the fourth and the fifth handle the training and the educational departments, respectively. The second assistant has, as his especial responsibility, the merchandise checkers, the collectors, the stock clerks, the cashiers and the interior mail and messenger service. The other non-selling assistant general manager supervises the receiving department, the department of money orders and adjustments, the supply department, the delivery, the receiving, the time office, the manufacturing, and sundry other smaller specialties of the store; small, however, only in a comparative sense. Taken by themselves they quickly would be seen to be sizable indeed. The tasks of most of these departments are fairly obvious from their names. Some of the others we shall see in a bit of detail as we go further into the store and its workings. In other chapters we shall describe what the great delivery department is supposed to accomplish, and actually does accomplish, the scope and plan and reach of the departments of training and of employment, and some others, too. It takes no great strain upon the imagination to conceive of the importance of the detective bureau's work, nor that of the superintendent of buildings. So much, then, for a preliminary bird's-eye view of a mammoth machine, not a machine for turning out shoes or typewriters or paper, but for buying and selling all these things and many, many more. And as you read in the earlier part of this book, the huge mechanism did not spring into its being in a year, or in a decade, or even in a generation. It represents slow, hard, steady growth; and slow, hard, steady growth it is still having.