An astragal joint consists of a soldered joint with ornamental mouldings, or astragals, round the pipe. A slip joint is simply one end of a pipe slipped into the end of another, which is enlarged to receive it. This is similar to that of an ordinary iron rain-water pipe. Expansion joints are of many kinds. An ordinary one is similar to a slip joint, but an indiarubber or asbestos ring is used instead of any packing or jointing material which would become hard. An astragal joint is generally used on outside lead soil pipes. Slip and expansion joints are used for waste pipes, but chiefly for those through which hot water passes.