| 释义 |
caisson|ˈkeɪsən, keɪˈsuːn|
Also 8 caissoon.
[a. F. caisson large chest, f. caisse chest. The first pronunciation is given by most orthoepists, the second (which agrees with the usual treatment of F. -on in the 18th c.) is given only by Perry, Worcester, and Cull.]
1. Mil.
a. A chest containing bombs or other explosives, to be buried and fired as a mine.
1704in J. Harris Lex. Techn. 1721Bailey, Caisson [in Fortification], a Chest of Wood holding four or 6 Bombs, or sometimes filled only with Powder, and buried under Ground, by the Besieged, to blow up a Work the Besiegers are like to be Masters of. 1755Johnson, Caisson, a chest of bombs or powder, laid in the enemy's way to be fired at their approach. 1772T. Simes Mil. Guide s.v.
b. A chest containing ammunition; a wagon for conveying ammunition. Also fig.
1704in J. Harris Lex. Techn. 1708Kersey, Caisson, a covered Waggon, or Carriage for Provisions, or Ammunition for an Army. 1730–6in Bailey. 1812Examiner 24 Aug. 532/1, 20 caissons of ammunition. 1865Bushnell Vicar. Sacr. iii. iii. 233 The retributive causes of nature roll out their heavy caisson with us. 1870Echo 14 Nov., Several artillery caissons captured at Orleans were found to be filled with wearing apparel.
2. Hydraulics.
a. A large water-tight case or chest used in laying foundations of bridges, etc., in deep water.
1753Chambers Cycl. Supp., Caisson is also used for a kind of chest used in laying the foundations of the piers of bridges. 1765Ann. Reg. 12/2 The greatest part of the first course [of the sixth pier of Blackfriars bridge] carried by the Caissoon. 1823P. Nicholson Pract. Build. 305 M. Labelye erected the piers [of Westminster Bridge] in caissons, or water-tight boxes. 1875B. Richardson Dis. Mod. Life 70 The effect of atmospheric pressure on men who are employed to work in caissons.
b. In Canal-making. Formerly, a large water-tight cistern or reservoir made at any point where the canal had to be extended over lower ground, in order to enable the boats to come forward with material for the embankment.
1769De Foe's Tour Gt. Brit. III. 272 At Stretford, three Miles off, is the Caisson 40 Yards long by 32. 1838Southey Lett. (1856) IV. 546. 1861 Smiles Lives Eng. I. 382 Brindley..had the stuff required to make up the embankment brought in boats..conducted from the canal along which they had come into caissons or cisterns placed at the point over which the earth and clay had to be deposited.
c. A vessel in the form of a boat used as a floodgate in docks.
1854Fairbairn in Proc. Inst. C. Engin. 9 May, The employment of caissons for closing the entrance to wet or dry docks. 1867Smyth Sailor's Word-bk., Caisson, a vessel fitted with valves, to act instead of gates for a dry dock.
d. ‘A sort of float sunk to a required depth by letting water into it, when it is hauled under the ship's bottom,..and on pumping out the water floats her’ (Smyth Sailor's Word-bk.); = camel n.
1811Naval Chron. XXV. 219 This caisson or floating dock is made of wrought iron.
3. Arch. ‘A sunken panel in ceilings, vaults, and cupolas’. Gwilt Encycl. Archit.
4. attrib. and in comb., as caisson disease (see quots.); caisson-gate = sense 2 c. caisson sickness = caisson disease.
1866Cornh. Mag. Mar. 381, 23 feet depth of water when the caisson-gates are opened. 1883Harper's Mag. July 945/1 The ‘caisson disease’ is the result of living under atmospheric pressure greatly above that to which the human system is normally adapted. 1887Health 11 Mar. 394 What is known as the ‘caisson disease’ is not produced by the mere increase of atmospheric pressure, but by the sudden diminution of it on leaving the caisson, which produces ruptures of small blood-vessels. 1911Engineer 10 Mar. 243 Caisson Sickness and Compressed Air.
Hence caissonier |keɪsəˈnɪə(r)|, one who works in a caisson; so ˈcaissoning.
1903Strand Mag. Jan. 98/2 The lives of ‘the men in the box’, i.e. the caissoniers, are in the greatest danger. Ibid. 101/2 After all these terrors it is perhaps astonishing to be told..that caissoning would be sought by any considerable number of men. |