102 Society of the Arts at Hamburgh. 



tage, and to render it by thefe means foluble in the acetous 

 acid. 



Citizen Berthollet communicated a notice on a particular 

 acid which he had difcovered, and to which he gives the 

 name of the zoonic acid, becaufe it is extracted eiTentially 

 from animal fubftances. (Seepage 68 of this Number.) 



Citizen Dolomieu read a memoir on the tourmalines 

 found in Mount St. Gothard, the object of which was to ex- 

 amine, how far colour, confidered as a character of ftone, 

 can determine its nature ? 



Laftly, the new experiments of Citizen Vauquelin, on the 

 red lead of Siberia, and the new earth which he found 

 in the beryl, or aigtte marUi i were the fubject of another 

 memoir. 



HAMBURGH, 



THE fociety for promoting the arts and ufeful manufac- 

 tures have propofed a prize of 40 ducats, to be given to the 

 author of the beft anfwer to the following queftion : 



<l What are the beil means, confirmed by experience, to 

 fecure wooden work wafh-'d by the fea, fuch as flukes, 

 buoys, fignals for fhips, &c. and even mips themfelyes, from 

 being deftroyed by the ihell-worm (teredo tiavalis), which, 

 as is well known, pierces through wood and haftens its 

 decay ?" 



The fociety will confider that eflay as the beft, which pro.- 

 pofes means of a cliesp nature, known by experience to be 

 effectual, and which are either -as durable as the wood 

 itfelf to withftand the effects of the waves and the ice, or 

 ean be renewed from time to time without inconvenience, 

 and without injury to the works they are intended to pre- 

 ferve. All the means hitherto propofed for the like pur- 

 pofe, fuch as covering the wood with copper, lead, &c r are 

 excluded from the prize ; becaufe thefe, beftdes being pe- 

 rifhahle in water, are liable to be ftolen, and in many cafes 

 frannot be applied. No paper, alfo, can be entitled to the 

 prize, unlefs the means propofed in it have been proved by 



experience 



