pole plate

• pole-plate

pole plate (plural pole plates)

1. A horizontal timber resting on the tiebeams of a roof and receiving the ends of the rafters, differing from the plate in that it is not resting on the wall.
   • 1853 July, R.S. Burn, “Agricultural Architecture and Engineering”, in The Journal of Agriculture, volume 6, page 16:

     The "pole-plate" is parallel to the wall-plate, and rests on the end of the "tie-beam." The "purlin" is a piece of timber running parallel to the pole-plate, and midway between it and the "ridge-pole," the purlins resting on the principal rafters.

   • 1856, John White, Rural Architecture, page 7:

     The roofs of the dormer windows are supported on a beam or pole plate, running level between the front wall and the rafters of the principal roof ; this beam may be 6 inches broad and 4 inches thick; the space between the front wall and the roof may be built up with brick, and finished on the outside with Roman cement, so as to correspond with the rest of the wall.

   • 1895, Edward J. Burrell, Elementary Building Construction and Drawing, page 122:

     The end of the common rafter is birdsmouthed and nailed to the pole plate .

2. Any of various plates used to secure an attachment to a pole.
   • 1906, Telephony - Volume 11, page 251:

     The pole plate normally has a greater radius than the largest pole top, and when drawn into place not only conforms closely to the circumference of the pole, but draws down against the gain, thus providing sufficient spring tension to compensate any shrinkage in the pole or cross arm.

   • 1918, Western Electric Company, Electrical Supply Year Book, page 522:

     A heavy three-hole pole plate with crossarm and porcelain elbow makes the bracket easy to put up and wire, serving also as a protection for the wires.

   • 1928, United States. Surgeon-General's Office, The Medical Department of the U.S. Army in the World War:

     The legs or feet to be stirrup shaped, extending 4 inches below the supporting surface of the pole plate to which they are attached.

3. (biology) A structure that forms at the pole of the spindle during the first meiotic or mitotic division in some animals.
   • 1899, Thomas H. Montgomery Jr., “The Spermatogenesis in Pentatoma up to the Formation of the Spermatid”, in University of Pennsylvania, editor, Contributions from the Zoological Laboratory for the year 1898:

     The pole plate of the 1st spindle becomes immediately the equatorial of the 2nd, where the 14 chromosomes are arranged in pairs, of each of which one goes to one pole and one to the other.

   • 1911, Edmund Beecher Wilson, The Cell in Development and Inheritance:

     In Spriochona (Fig. 38, A-C) a hemisperical "end-plate" or "pole-plate" is situated at either pole of the spindle, and Herwig's observations indicated, though they did not prove, that these plates arose by the division of a large "nucleolus."

   • 1917, Calvin Olin Esterly, The Feeding Habits and Food of Pelagic Copepods, page 133:

     As the chromosomes near the poles they apparently fuse with the pole plate (pl. 17, fig. 16), the number of chromosomes remaining distinct until after the formation of the new nuclear membrane (figs. 17m 18).