Fuente: WIPO "rice" 10,751. Clark, R. O. May 18, 1907, [date applied for under Section 91 of Patents &c. Act, 1907]. Earthenware pipes intended to replace cast-iron or steel gas or water mains are made from one- and-a-half to four or five times the usual thickness so as to be able to withstand high pressures. Sleeve joints.-The pipes have broad grooves G near the ends and roughening grooves F, and are butted together within a sleeve B into which cement is introduced through openings M. The sleeve may be in one piece, or in halves having interlocking-grooves and lugs of tapered form to hold the parts together, and may have a lip H or internal lugs (not shown) to support the pipe ends in alinement..