TAR 



TAX 



and its legs are concealed by the hollow 

 figure of a man whose chin is on a level 

 with the bend of the siphon, so that the 

 figure stands, like Tantalus in the fable, 

 up to the chin in water, but unable to 

 quench his thirst. 



TANY'STOMA (rai/uo), to stretch, 

 cTo/jia, the mouth). A section of dip- 

 terous insects, which have a projecting 

 proboscis, with the last joint of the an- 

 tennae undivided. To this section be- 

 longs the Gad-fly tribe. 



TAP-ROOTED. Fusiform. A desig- 

 nation of that kind of root which consists 

 of one fleshy elongated centre tapering 

 to the extremity. This is termed 

 pivotante by the French. 



TA'PIRID^. The Tapir tribe; a 

 group of Pachydermatous animals, differ- 

 ing from the Suidae, or Pig tribe, in the 

 presence of only three toes on each hind 

 foot, and sometimes also in the front, and 

 in the absence of a central cleft of the 

 foot. 



TAPITE'LiE {tapetum, a carpet, tela, 

 a web). A family of spiders, which spin 

 great webs of a close texture like ham- 

 mocks, and wait for the insects which 

 may be entangled therein. 



TA'RDIGRADA {tardus, slow, gradus, 

 a step). A group of the Edeiitata, or 

 toothless animals, distinguished from the 

 true edentata by the peculiar shortness 

 of the muzzle. They are characterized 

 by the slowness of their motion, and con- 

 tain the sloths, in which Cuvier ob- 

 serves that " nature seems to have 

 amused herself with producing some- 

 thing imperfect and grotesque." 



TARE, TRET, CLOFF, &c. These 

 terms, though specially of commercial 

 importance, are found in treatises of 

 arithmetic, and must therefore be briefly 

 noticed. 1. Tare, derived from the Italian 

 tar are, to abate, is the allowance made 

 for the box or bag in which goods are 

 packed. 2. Tret, probably derived from 

 the Italian tritare, to crumble, is an 

 allowance of 41bs. in 1041bs. for waste. 

 3. clnff, or clough, defined to be that 

 wherein any thing is put for carriage 

 sake, is an allowance of 21bs. in 3c wt., 

 in order tliat the weight may hold good, 

 when the article is sold by retail. 4. Chross 

 weight, is that of the goods and the 

 package taken together. 5. Suttle, pro- 

 bably derived from the Italian sottile, 

 fine or valuable, denotes the weight 

 which remains, when the tare only is 

 allowed : it is the finer part, separated 

 from the coarser. 6. Net, from the Italian 

 329 



netto, signifies the weight which remains 

 when all allowances are made. 



TARRAS or TERRAS. A volcanic 

 earth, found in Germany and Sweden, 

 and, when pulverised, used as a cement. 

 It does not differ much from puzzolana, 

 but it is much more compact, hard, 

 porous, and spongy. 



TARSI. The feet in insects, which 

 are articulated, and formed of five or a 

 less number of joints. 



TARTAR. Bitartrate of potash; a 

 salt deposited on the sides of casks dur- 

 ing the fermentation of wine, owing to 

 its insolubility in alcohol. This is crude 

 tartar, and it is also called argol ; when 

 purified, it is called cream of tartar. 



TARTARIC ACID. A bibasic acid, 

 existing in many fruits, and also as tar- 

 trate of lime in several roots, but pre- 

 pared only from the juice of the grape, 

 which contains tartaric acid in the form 

 of tartar or bitartrate of potash. 



TARTARINE. The name given by 

 Kirwan to the vegetable alkali, or potash. 



TARTRATE. A neutral compound 

 of the tartaric acid with a base. 



TAURUS. The Bull; the name of 

 the second zodiacal constellation, con- 

 sisting of 141 stars, the principal of 

 which is Aldebaran. It denotes the 

 second month of autumn, extending 

 from the 20th of October to the 20th of 

 November, and the period of tillage in 

 Egypt, when other countries have done 

 sowing. 



TAURUS PONIATOWSKI. A mo- 

 dern northern constellation, consisting 

 of seven stars, formed by a Polish astro- 

 nomer, the Abbe Poczobut, in the year 

 1778. It is situated between Aquila and 

 Ophiuchus. 



TAU'TOCHRONE [rairo, the same, 

 xpovoi, time). A term in Mechanics for 

 a curve line having this property, that a 

 heavy body descending along it by the 

 action of gravity will always reach the 

 lowest point in the same time, from 

 whatever point in the curve the body 

 begins to descend. This is, under cer- 

 tain circumstances, the property of the 

 cycloid. 



TAU'TOLITE. A crystalline mineral, 

 said to consist of silicate of protoxide of 

 iron and silicate of magnesia, and found 

 in the volcanic rocks of the lake of 

 Laach, near Bonn, on the Rhine. 



TA'XICORNS (taxus, the yew, cornu, 

 a horn). A family of coleopterous in- 

 sects, in which the antennae gradually 

 increase in size as they extend from 



