The side posts of doors. Mr. T. N. Parker having noticed how rapidly the lower ends of door-posts decayed where they are exposed to wet, contrived a cast-iron socket for them, which is much used in Shropshire, and might be generally introduced with advantage. The sketch in the subjoined cut represents one of them beautifully cast by the Colebrook-Dale Company; the weight of them is only 71bs. the pair, and they are retailed in Oswestry at 2 1/2d. the pound. When the increased durability and strength conferred by these metal sockets, to an important part of a building, is considered, then trifling cost will not, we think, form an impediment to their employment.