T E S 



T E S 



to tlie court of Vienna, where he remained two years. He 

 ■was chofcii by the iiobihty fpeaker at the famous diet of 

 1738, on which occafion he obtained, in recompence of liis 

 conduct, a gold medal, bearing on one fide his crell, and on 

 the other the motto " Confcius Refti." He was appointed 

 in 1739 to conduAan embaily from this diet to France, and 

 refided at Paris till the year 1742, concluding during this 

 interval an advantageous treaty of commerce with the king 

 of the^Two Sicilies, and terminating a fubfidiary treaty of al- 

 liance with France, by which Sweden was to receive in the 

 courfe of three years 27 tons of gold. In 1743 l>e was fent 

 to Denmark, and in the following year to Berlin, on bufi- 

 nefs of great importance. At Berlin he was honoured with 

 the Prulhan order of the Black Eagle. He occupied ieveral 

 other ftations of dignity and truft, the duties of which he 

 difcharged with Angular wifdom and fidelity. But the moft 

 important office alTigned him, was that of preceptor to the 

 crown prince, Guftavus HI., to which he was appointed in 

 1747. On this occafion he wrote his " Letters addreffed to 

 a Young Prince," for the ufe of his royal pupil, which 

 were afterwards tranflated into moft of the languages of 

 Europe. Retiring from public bufinefs in 1 76 1, he lived 

 on his eftate till the time of his death, which happened in 

 January 1770. Count Teffin was a zealous patriot and 

 enlightened citizen, and a diftinguifhed patron of letters. 

 With a view of encouraging the arts and fciences, he made 

 a great collcdtion of books, piftures, drawings, coins, and 

 other curiofities. But notwithftanding his various excellent 

 qualities, his enemies were affiduous in fruitlefs attempts to 

 throw a {hade over his charafter, as may be feen in a work 

 entitled, " An Hiftorical Account of the State of Sweden 

 under Frederic I," Gen. Biog. 



Tessin, in Geography, a town of the duchy of Mecklen- 

 burg ; 18 miles S.E. of Roftock. 



TESSIURSAK, an ifland near the W. coaft of Weft 

 Greenland. N. lat. 61° 10'. W. long. 47° 30'. 



TESSOUA, aconfiderable town of Africa, in the coun- 

 try of Fezzan ; 100 miles E.S.E. of Mourzouk. Near 

 this town, a river, now overwhelmed by the moving fands, 

 but formerly a deep and rapid ftream, had its courfe. 



TES80UELLE, a town of France, in the department 

 of the Mayne and Loire ; 5 miles S. of Chollet. 



TESSUA, a town of Hindooftan, in Rohilcund ; l8 

 miles S.S.E. of Bereilly. 



TESSUE, a town of Perfia, in the province of Adir- 

 beitzan ; 50 miles W. of Tauris. 



TESSUNTEE,' a town of the ftate of Georgia ; 80 

 miles W. of Tugeloo. 



TESSUT. See Teceut. 



TESSY, a town of France, in the department of the 

 Channel ; g miles S. of St. Lo. 



TEST, in Metallurgy, is a veflel of the nature of a cop- 

 pel, ufed for large quantities of metals at once, and formed 

 of the fame materials. 



The coppels, or fmall vefTels, ferve for operations of this 

 kind, when fmall quantities only are concerned ; but when 

 larger are worked on, veflels of a larger fize and coarfer 

 texture are employed, which are diftinguifhed by the name 

 of tejls. 



1 hefe are ufually a foot and half broad, and are made of 

 wood-aflies, not prepared with fo much care as for coppel- 

 making, and mixed with finely powdered brick-duft ; thefe 

 are made into the proper (hape, either by means of a (hallow 

 veflel, made of crucible earth, or caft-iron, of proper dimcn- 

 fions, or only an iron ring, or hoop, with three bars arched 

 downwards acrofs the bottom, about two inches deep, and 

 of different widths, from three or four inches to fifteen or 



more, according to the quantity of metal to be teftcd at 

 once. 



To make them in the firll manner, an earthen veffcl is 

 to be procured, not glazed within, and by its dcptli and 

 breadth proportioned to the quantity of metal to be worked ; 

 the infide of tins veffcl is to be well moiftcned with fair wa- 

 ter, that tlie allies to be put into it may adhere the better. 

 Put into this velRl, thus prepared, the aflies and brick-duft 

 before-mentioned, ajul firll moiilened either with water alone, 

 or witii water with a little white of an egg mixed in it ; let 

 the quantity of this be fo much as will h.-ilf fill the veffel, 

 then prefs the niafa witii a wooden indented peiUe, or, if not 

 for a very large tell, with a wooden cylinder, only of an inch 

 thick : when thus preil'ed down add frefli afhcs, and prefs 

 them a fecond time, as in the making of coppels, and re- 

 peat this addition of frefh afhcs till the earthen velTcl be 

 nearly full ; then remove the fuperfluous afhcs witli an iron 

 ruler, and let the inequahties remaining at the border be 

 fmoothed with a wooden or glafs ball rolled round about. 

 This done, you are to cut the cavity with a bowed iron, 

 that you may have a broad fpherical fegment, not very deep ; 

 and laftly, Ijy means of a lievc, ftrew this cavity carefully 

 and regularly over with dry allies of bones of animals, ground 

 extremcJy fine, and fqueezc tliefc hard in, by the rotation 

 of the wooden or glafs ball. Thus you have a teft finilhcd, 

 which, together with its earthen pot, muft be fet in a dry 

 warm place. 



To make the lefts in the other manner, or by means of 

 an iron ring ; let a ring of that metal be filled with afhes 

 mixed with brick-duft, and moiftencd as before mentioned, 

 in fuch manner that they may rife confiderably above the 

 ring'; then prefs them ftrongly either with your hands, or 

 with an indented peftle, and afterwards, with gentle blows 

 of a rammer, prefs the afhes from the circumference toward 

 the centre, in a fpiral hne, and that in fuch manner, that, 

 after having been fufficiently prefled, they may be a fmall 

 matter higher than the brink of the ring. If there are now 

 any vacancies in the mafs, empty the ring, and fill it again 

 with more afhes ; for if you fhould attempt to fill up thefe 

 by adding, were it but ever fo little, afhes, the fecond, or 

 additional quantities, will never cohere fo firmly with the 

 firft, but that they may probably fjeparate in the operation. 



This done, turn the ring upfide down, and on the other 

 fide, or bottom, take out the afhes to the quantity of one- 

 third part of the depth of the ring, and again fill the va- 

 cuity with the fame afhes, in fuch a manner that there may 

 remain no fenfible cavity. 



When the mafs is thus prepared, cut out a cavity in the 

 larger furface of the ring, with a bowed iron, as in the 

 former method. 



The Germans have, befide thefe, another kind of tefts, 

 which they call tre'tbfcherben. Thefe are a fort of veffcls 

 which refill the moft violent fire, and are fo extremely com- 

 paft, that they fometimes will retain not only melted metals, 

 but even the glafs of lead itlelf. 



The figure and fize of thefe vefTels may be the fame with 

 that of the coppel, but they arc ufually made larger ; and 

 the great difference of thefe tefts from coppels, and from 

 the ordinary tefts, which are indeed only a kind of large and 

 coarfe coppels, is, that the matter of thefe is more compaft 

 and coherent. 



The matter for making thefe tefts is thus prepared : take 

 of the pureft and fineft clay a fufficient quantity, make it 

 into balls, and dry them either in the air, or on the fire ; 

 when dried, beat them to powder in a mortar, and pour on 



the powder a gieat quantity of warm water ; let this mix- 

 ture reft a while, and when the clay has fubfided, pour off 

 3 C 2 the 



