Billiard table ivory balls from warping. The first use of electric heating was for an 18.2 balkline tournament held in December 1927 between Welker Cochran and Jacob Schaefer, Jr. The New York Times announced it with fanfare: "For the first time in the history of world's championship balkline billiards a heated table will be used..." A pool table, or pocket billiards table, has six – one at each corner of the table () and one at the midpoint of each of the longer sides ( or ). Pool tables come in different sizes, typically referred to as , , , or tables.
Billiard table between slates is filled with a hard-drying putty, epoxy or resin, then sanded to produce a seamless surface, before being covered with the cloth. When several pieces of slate are joined poorly it is possible for the resin to deform and cause an uneven playing surface; it can also be difficult to move once joined. Tables for the home market usually use slate beds as well, but the slate is often thinner, down to about . The early table beds were made of cloth-covered wooden boards. Today, inexpensive but not very rigid or durable materials used for the beds of