[Illustration] That means he used a long club called a sap, to turn the wheels that set the hand brakes on each car. The catwalks or decks along the car roofs made a path for the brakemen. Sometimes they walked up and down inspecting the train. Then they said they were “deckorating.” Fast freight cars, and slow ones, too, now have air brakes which are squeezed against the wheels by compressed air. Every car has an air hose that runs underneath it to the brake machinery. The hose from each car can be joined to the hose on the ones behind and in front, and finally to the locomotive’s hose. A pump in the locomotive compresses the air for the whole train. Now if the engineer wants to stop, he just moves a lever. A whoosh of air tightens the brakes on every car. When the train goes down a long hill, the squeezing of the brakes can actually make the wheels get red hot. Some freight trains have to stop and let the wheels get cool. But the cars in Sam’s train have a sort of fan built into the brake machinery. The fan cools the wheels, and the redball freight goes right on down. After a while, Sam takes a little scoop and tosses some sand into the firebox. He knows that the engine’s flues are likely to get clogged up with soot, and the sand will clean them out. Later on, sand does an even more important job. The train has run into a storm in the cold, high mountains. Slushy snow has frozen on the rails. Instead of pulling ahead, the engine’s wheels begin to slip round and round. But the engineer fixes that easily. He squirts sand onto the slick track to make the wheels pull again. The sand comes from the dome, which is the hump you can see behind the stack on top of a locomotive. Pipes lead down from the dome on each side and aim the sand onto the track just in front of the driving wheels. A locomotive’s sand is just as important as coal and water. Ice or rain or even the dampness in a tunnel can make slippery tracks. So the railroads keep supplies of fine dry sand to fill the domes. Sam always checks to see if he has enough sand when the tender takes on coal. [Illustration] [Illustration: STOP SWING BACK AND FORTH ACROSS TRACKS REDUCE SPEED HELD AT ARM’S LENGTH HORIZONTALLY PROCEED RAISED AND LOWERED VERTICALLY] The huge coal towers in big freight yards can fill several tenders at once. Often, while the loading goes on, ashes from the locomotive’s firebox get cleaned out at the same time. There is a dump pit under the tracks, with little cars that run on their own rails. After a little car is filled with ashes, it can be pushed away and unloaded at the ash heap. When Sam pulls into the next big freight yard, his part of the run is finished. After a while he will board another engine and take another freight train back to his home station. He has a regular schedule for work. That doesn’t seem strange these days, but Sam’s grandfather would have thought it was something miraculous.