| 释义 |
▪ I. berm|bɜːm|
Also 8–9 berme, 9 birm.
[a. F. berme, a. MDu. and Ger. berme, in mod.Du. berm, in same sense; prob. cognate w. ON. barmr brim, edge, border of a river, the sea, etc.]
1. a. A narrow space or ledge; esp. in Fortif. a space of ground, from 3 to 8 feet wide, sometimes left between the ditch and the base of the parapet.
1729G. Shelvocke Artillery iv. 197 Round which shall be formed a Berm or Ledge, for the conveniently ranging of certain Paper Tubes or Cases. 1775R. Montgomery in Sparks Corr. Amer. Rev. (1853) I. 470 By the time we arrived there, the fraise around the berme would be destroyed, the rampart in a ruinous state. 1816C. James Milit. Dict. (ed. 4) 248/2 Berm..is to prevent the earth from rolling into the ditch, and serves likewise to pass and repass. As it is in some degree advantageous to the enemy, in getting footing, most of the modern engineers reject it. 1850Alison Hist. Europe X. lxviii. §49. 335 The ladders..enabled them to reach an intermediate ledge or berm.
b. spec. in Geol. (See quots.)
1931F. Bascom in Science LXXIV. 172/1 The word berm..should be used to distinguish those terraces which originate from the interruption of an erosion cycle with rejuvenation of a stream in the mature stage of its development. 1942C. A. Cotton Geomorphology (ed. 3) xviii. 242 The term ‘berm’ has been introduced for any remnant of a surface developed to full maturity in a cycle that has since been interrupted. Though it has been said to be a kind of ‘terrace’, a berm may include more than the valley floor which becomes a true river terrace. 1942O. D. von Engeln Geomorphology xii. 221 Such a remnantal flat, which has a surface slope downstream, may be called a strath or sometimes, together with the valley shoulder, a berm.
2. berm-bank, the bank of a canal opposite the towing-path. [? Actually used only in U.S.A.]
1854N. & Q. Ser. i. X. 12/2 [A writer from Philadelphia] The bank of a canal opposite to the towing-path is called the birm-bank. 1877Engineer 3 Aug. 89/1 To lay a rail upon the berme bank (the bank opposite the towing path).
3. A ledge or flat of land bordering either bank of the Nile and inundated when the river overflows.
1891Daily News 31 Oct. 6/4 To raise the Nile at the apex of the Delta to a level sufficient to flood the islands and berms of the two branches in the Delta. 1900Westm. Gaz. 10 July 2/2 The water level in the winter was some fifty centimètres below the general level of the berm.
▪ II. † berm(e, v. Obs.
[ME. berm-en, f. berme, barm n.2 An earlier form of barm v.]
trans. To work out, as barm: to purge out.
c1315Shoreham Poems 15 Ine the foreheved the crouche a set Felthe of fendes to bermi. c1440Promp. Parv. 32 Bermyn or spurgyn as ale, spumo.
▪ III. berm(e
obs. form of barm. |