The shipper delivers the goods at the receiving freight-house of the railway company. His cartman gets a receipt from the tallyman. This receipt may be sent direct to the consignee, or more frequently is exchanged for a bill of lading. There the responsibility of the shipper ends. His goods are in the hands of the railway company, which to all intents and purposes guarantees their safe and prompt delivery to the consignee. The tallyman's receipt is taken in duplicate. The latter is kept in the freight-house until the freight is loaded in a car, and is then marked with the initials and number of the car into which the freight has been loaded. After that it is taken to the bill clerk in the office, and from it and others is made the waybill or bills for that particular car. Where the volume of freight received at a given station is large, it is customary to put all packages for a common destination, as far as possible, in a car by themselves, thus making what are termed "straight" cars. This is not always possible, however, or if attempted would lead to loading a very large number of cars with but light loads. So that it becomes necessary to group freight for contiguous stations in one car, and again often to put freight for widely distant cities in the same car. These latter are known as "mixed" cars. We will assume the day's receipt of freight finished, and most of the cars loaded. About 6 P.M. the house will be "pulled," that is, those cars already loaded will be taken away, and an empty "string" of cars put in their place. An hour later, this "string" will in turn be loaded and taken out, and the operation repeated, until all the day's receipt of freight is loaded. Meanwhile other freight will have been loaded direct from the shippers' carts on to cars on the receiving tracks. For all cars, there is made out in the freight-office a running slip or memorandum bill, which gives simply the car number, initials, and destination. These are given to the yardmaster or despatcher, and from them he "makes up" the trains. To a very great degree, the good movement of freight depends upon the vigilance of the yardmasters and the care with which they execute their duties. In an important terminal yard, the yardmaster may have at all times from one to two thousand cars, loaded and empty. He must know what each car contains, what is its destination, and on what track it is. To enable him to do this, he has one or more assistants, day and night. They, in turn, will have foremen in charge of yard crews, each of the latter having immediate charge of one engine. The number of engines employed will vary constantly with the volume of the freight handled, but it is safe to assume that there will be at all times nearly as many engines employed in shifting in the various yards and important stations on a line as there are road engines used in the movement of the freight traffic.