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XLI. Preparnt'inn of a vcw Lrif'nig proper to h used in 

 all chemicnl Operations. Li/ C. Paysse, Professor of 

 Chemistnj*. 



JLt is generally admitted that the rapid progress which clie- 

 mistrvha=; made during the last tweiitv years, is in part owing 

 to the different kinds of apparatus invented hythe ininiortal 

 Lavnisier, and the precautions. employed in the art of luting. 

 In this point of vnew lutings have been of essential service 

 to chemists, since bv facilitatin<i; the condensation of many 

 aeriform products they have afl'orded us the means of de- 

 tennining iheir naiure, and appreciating their volume as 

 veil as their gravity. This truth did not escnpe the sagacity 

 of the celebrated chemist Chaptal, who in liis Elements of 

 Chemistry says : " On the art of lutino; an apparatus pro- 

 perly the whole succc'ss of an operation depends." 



Among the substances most used for this purpose, are 

 reckoned the fat luting paste of almonds or of linseed, the 

 oil of which is extracted, and mixed with strong glue, and 

 that of the white of egsrs, and new cheese united to lime. 

 These different kinds of luting are attended with inconve- 

 niences which render them improper for being employed 

 under all circumstances. Fat luting for example, composed 

 of <lry clav and oil, con)bined with an oxide of lead, can- 

 not be applied but on parts v.hich receive a weak impression 

 from the heat ; for they liquefy at a low temperature, soon 

 run, and consequently become unfit for the proposed end : 

 that of linseed and almonds, mixed with glue or gelatine, 

 is often too porous, easy to be destroyed by acids, and by 

 annnonia, when in a gaseous state : those prepared with 

 tb.e white of c^z^, and cheese, mixed with lime, are only 

 attended with Ihe inconvcnienev of becoming too soon 

 solid, and inunediately after mixture; so that it is exceed- 

 ing! v difficult to apply them. 



The necessity I was under, in preparing oxvcrenated mu- 

 riatic acid on a large scale, to Hud a lutina" which to the 

 advantage of being cheap should unite that of being soon 

 prepared, and of resisting; the destructive action of the va- 

 pours of that acid, ami that strong action of heat which 

 Uie luted part is often r.bhged to sustain ; of being easily 

 applied, and in an uniform manner, without too speedily 

 becoming hard, induced me to make some researches^ whicU 

 furnished me with the most satisfactoiy result, 



* From Annalci de Chim;t\ No. 157, 



After 



