TENT 977 



Teeth imported in 1 873 : Elephant, Sea-cow, Sea-horse. 



TELEGRAPHS. See ELECTRO-TELEGRAPHY. 



TELLURIC BISMUTH. A telluride of bismuth. See TETBADTMITE. 



TELLURIUM. One of the elementary bodies, usually classed amongst the motals, 

 but it presents so great an analogy to sulphur and selenium, that many are disposed 

 to remove it from the metallic bodies. 



Tellurium was originally found in Transylvanian gold ores ; and more recently it 

 has been found with bismuth. Tellurium has a silvery lustre ; its texture is crystalline 

 and brittle. Its specific gravity is 6'65, and its atomic weight 64'5. From its 

 extreme rarity, and consequent cost, it has not yet found any application in the arts. 



TEMPERING OP STEEL. In metallurgy the process by which a certain re- 

 quired character is given to steel or any other metal. 



The process of hardening or tempering steel is performed with due relation to 

 the quality of the steel and the purposes for which it is designed. In most instances 

 the hardening is effected in water and brine : saw-blades are thus hardened, after 

 being heated in melted lead ; and sabres are heated in a choked fire of charcoal, and 

 then swung rapidly through the air. Mint-stamps are hardened in oil. The common 

 method of procedure in hardening is this : The steel is overheated, cooled in cold 

 water, and then annealed or tempered, by being so far re-heated that oil and tallow 

 will burn on its surface ; or the surface is ground and polished, and the steel re- 

 heated until it assumes a certain colour. The gradations of colour consecutively 

 follow : a light straw-yellow, violet, blue, and finally grey or black, when the steel 

 again becomes as soft as though it had never been hardened. 



TEMPLET. A gauge formed from a thin piece of metal, as a guide to the form 

 of the work to be executed. 



TENT. A portable lodge, consisting of canvas sustained by poles and stretched 

 by cords, used for sheltering men, especially soldiers in camp, from the weather. 

 Tents were commonly used in the earliest periods of man's history. The patriarchal 

 tribes dwelt in tents. Layard describes one of the sculptured stones at Mosul as re- 

 presenting Sennacherib seated on a throne, placed at the entrance of a city. Behind 

 the king was the royal tent supported by ropes, and an inscription, signifying ' This is 

 the tent of Sennacherib, King of Assyria.' This was 700 years before Christ. We 

 learn that Paul was a tent-maker, therefore in those days it was an important calling. 



We have no space to enter into the history of tents or describe the varieties which 

 have been used from time to time. A few words on modern tents must suffice : 



The hospital marquee is 29 feet long and 14 feet wide and 15 feet high. This is 

 supposed to accommodate not less than eighteen or more than twenty-four men. The 

 height of each tent-pole is 13 feet 8 inches ; the length of the ridge-pole 13 feet 10 

 inches ; the height of the tent-walls from the ground 5 feet 4 inches. The weight 

 of all the material of such a tent is stated by Major Ehodes to be 652 Ibs. 



The ventilation of tents has been admirably effected by Mr. Doyle, to whom we 

 are indebted for the information contained in the following notes on the subject. 



The old method of ventilating military tents was very defective. Ventilating 

 openings were made at ihe top of the tent, but no means were provided for the 

 admission of fresh air. The result was most unsatisfactory, as may be gathered from 

 the following evidence given before the Sebastopol Committee : 



' The tents were very close indeed at night. When the- tent was closed in 



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