106 Premiums in Chemistry, fyc 



who shall invent and discover to the Society 

 a method, verified by actual experiments, of 

 increasing the quantity or force of steam, in 

 steam-engines, with less fuel than lias hitherto 

 been employed, provided that in general the 

 ■whole amount of the expenses in using steam- 

 engines may be considerably lessened } the 

 gofd medal, or thirty guineas. To be com- 

 municated to the Society on or before the first 

 Tuesday in January, 1305. 



9?. Substitute for Tar. To the person 

 •who shall invent and discover to the Society 

 the best substitute for Stockholm tar, equal in 

 all its properties to the best of that kind, and 

 prepared from materials the produce of Great- 

 Britain ; the gold medal, or one hundred gui- 

 neas. A quantity of the substitute, not less 

 than one hundred weight, with certificates 

 that at least one ton has been manufactured, 

 and that it can be afforded at a price not ex- 

 ceeding that of the best foreign tar, together 

 with an account of the process, to be delivered 

 to the Society on or before the first Tuesday in 

 March, 1805. 



98. Preparation of Tan. To the per- 

 son who shall prepare in the most concen- 

 trated form, so as to be easily portable, and 

 at a price applicable to the purposes of manu- 

 factures, the largest quantity, not less than one 

 hundred weight, of the principle called by the 

 French tannin, which abounds in oak-bark 

 and many other vegetable substances ; the gold 

 medal, or fifty guineas. Certificates of the 

 superior quality of the quantity so prepared, and 

 a sample of not less than 281b. to be produced 

 to the. Society on or before the last Tuesday in 

 January, 1805. 



99. Indelible Ink. To the person who 

 shall discover to the Society, a method of 

 making a black ink proper lor writing, supe- 

 rior to any at present known* indestructible by 

 chemical applications, and not dearer than 

 that which is now in common use ; the silver 

 medal or fifteen guineas. Certificates that not 

 less than two gallons of such ink have been 

 actually prepared and found to possess the 

 qualities above mentioned, with a full detail of 

 the process of making it, and two quarts of the 

 ink, to be delivered to the Society on or before 

 the second Tuesday in January, 1805. 



100. Preparation of a red Stain for 

 Cotton Cloth. To the person who shall 

 communicate to the Society, the cheapest and 

 most effectual method of printing or staining 

 cotton cloths with a red colour, by an imme- 

 diate application of the colouring-matter to the 

 cloth, equally beautiful and durable with the 

 red colours now generally procured from de- 

 coctions of madder ; the gold medal, or thirty 

 guineas. Certificates that the above process 

 has been advantageously used on ten pieces of 

 calico, each twenty-one yards or upwards in 

 leugtb, one piece of the calico so printed, a. 



quart of the colour in a liquid state, and % 

 full account of the preparation and applica- 

 tion, to be produced to the Society on or be- 

 fore the second Tuesday in January, 1805. 



101. Preparation or a green Colour 

 for printing CottOn Cloth. To the per- 

 son who shall communicate to the Society the 

 best and cheapest method of priming with a 

 full green colour on cotton cloth, by an im- 

 mediate application of the colouring matter 

 from a wooden block to the cloth, equally 

 beautiful and durable as the colours now formed, 

 from the complicated process of the decoction 

 of weld on alumine and the solutions of in- 

 digo by earths or alkaline salts ; the gold medal, 

 or thirty guineas. Certificates and conditions 

 as for premium 100. 



102. Substitute for the Basis of 

 Paint. To the person who shall produce to 

 the Society the best substitute, superior to any 

 hitherto known, for the basis of paint, equally 

 proper for the purpose as the white lead now 

 employed ; such substitute not to be of a noxi- 

 ous quality, and to be afforded at a price not 

 materially higher than that of white lead ; the 

 gold medal, or one hundred guineas. A quan- 

 tity of the substitute, not less than 50lb. weight, 

 with an account of the process used in preparing 

 it, and certificates that at least one hundred 

 weight has been manufactured, to be produced 

 to the Society on or before the first Tuesday in 

 January, 1805. 



103. Red Pigment. To the person who 

 shall discover to the Society a full and satis- 

 factory process for preparing a red pigment, fit 

 for use, in oil and water, equal in tone and 

 brilliancy to the best carmines and lakes now 

 known or in use, and perfectly durable ; the 

 gold medal, or thirty guineas. One pound 

 weight of such colour, and a full disclosure of 

 its preparation, to be produced to the Society 

 on or before the first Tuesday in Feb. 1805. 



A 7 . .B. It is not required that the colour 

 should resist the action of fire or chemical ap- 

 plications, but remain unaltered by the com- 

 mon exposure to strong light, damps, and noi- 

 some vapours. 



1 04. 4 U lt r a m a b i n e . To the person who 

 shall prepare an artificial ultramarine, equal in 

 colour, brilliancy, or durability, io the be6t 

 prepared from lapis lazuli, and which may be 

 afforded a"t a cheap rate; the gold medal, or 

 thirty guineas, The conditions are the same as 

 in the preceding premium for the red pigment. 



J05. Analysis of British Minerals. 

 To the person who shall communicate to the 

 Society, the most correct analysis of any mi- 

 neral production of Great-Britain, hitherto ei- 

 ther unexamined, or not examined with accu- 

 racy ; the gold medal. The analysis and suf- 

 ficient specimens to be produced to the Society 

 on or before the first Tuesday in Jan. 1805. 



106. Si a ti: a ry Marble. To the pers 



rson 



