Determining what is in your saddle can be tricky, but itâs important to know what youâre riding on. Wool flocked saddles will often have what is known as rear gussets (the seam along the back of the panel), although some foam saddles can have gussets to allow them to fit a broader backed horse.
Furnaces and boilers represent the two largest categories of heating systems used for houses and for buildings in general. The main difference between these two heating appliances is what they heat: Furnaces heat air that is distributed by a ductwork system. Boilers heat water that is used in different hydronic heating systems. So-called combi-boilers are designed to supply hot water for washing as well as for whole-house heating. Furnaces and boilers usually burn gas, propane or fuel oil. Less frequently, you'll find units that burn wood, pellet fuel or coal.
1 A fire where the coal burns. 2  A boiler full of water that the fire heats up to make steam.  A cylinder and piston, rather like a bicycle pump but much bigger. Steam from the boiler is piped into the cylinder, causing the piston to move first one way then the other.