12 Darracq's Obfervations 



rate the pafle under a dream of water, and to prepare a gluten 

 d from any amylaceous principle. But before 

 this object can be carried into execution, it will be neceflary 

 that various trials mould be made by artifts to ascertain whe- 

 ther the glutinous folution has the properties requifite for 

 painting, or at lead fojr varnilhing. 



Chemifts may, however, employ it in the. mean time as 

 lilting. I mixed with fermented gluten diluted in alcohol a 

 certain quantity of quicklime: ammonia and caloric were 

 difengaged, and the mixture aftumed a foft confidence. With 

 this pafte I luted feveral veflels, placed over them bands of 

 linen dipped in the folution of gluten, and befprinkled them 

 with quicklime: they foon adhered with fueh force that I 

 think this luting preferable to that prepared with the whites 

 of eggs. 



It appears to me lo refult from thefe exeperiments: 



I ft, That frefh gluten is infoluble in alcohol. 



2d, That it becomes foluble when it has undergone acid 

 fermentation. 



3d, That the alcoholic folution of gluten is precipitated 

 by water. 



4th, That this folution, evaporated to the confidence of 

 fyrup, furniihes a varnim which may be employed in the arts. 



5th, That fermented gluten diluted in alcohol becomes an 

 excipient of colouring matters^ and makes them adhere to 

 the fmootheft bodies. 



6th, That vegetable colouring fubftances combine with 

 gluten better than others. 



7th, That painting where gluten has been ufed dries very 

 foon, has no noxious odour, and may be warned, 



8th, That a very ftrong and tenacious luting may be made 

 with gluten and lime. 



III. Observations on the Acetic and Acetous Adds, Bjr 

 C. Darracci*. 



J. HE numerous opinions of chemifts on the difference 

 between the acetic and acetous acids have induced me to 

 make a few researches on the fubjeft. But before I give an 

 account of my experiments I (hall mention a few of thofe of 

 the modern chemifts, and alfo the conclufions which they 

 have drawn from them. 



C. Adet read a memoir in the Tnftitute, on the nth Ther- 



* Fiom the Annates dc Cbimie, No. 122. 



midor, 



