3f)8 SCIENTIFIC CONGRESS OF CARLSRUHE. 



in consideration of the small number of zoologists present, coalesced 

 with the section of anatomy;) Medicine; Surgery; Ophthalmology and 

 gyn cekology ; Psychiatrics . 



The transactions which we propose for special notice on this occasion 

 arc those of the fifth and sixth sections, (physics and chemistry.) 

 These two sections held their meetings in the amphitheaters of the 

 Polytechnic Institute, a vast establishment, frequented annually by 

 more than 600 pupils from different parts of Germany and the Scandi- 

 navian islands, but whose buildings are not yet sufficiently spacious 

 for the reception of all the collections. The largest part is assigned 

 to chemistry, which, under the superintendence of the learned pro- 

 fessor, M. Weltzien, forms a very important portion of the course of 

 instruction at the Institute. 



In what follows will be found a sketch of the principal facts sub- 

 mitted to the sections, whose proceedings we have undertaken to 

 report. 



II. Section of Chemistry. 



A Solvent of Cellulose and of Silk — Apparatus for Preparing Ozone — Anemonine and 

 Anemonic Acid — Preservation of Wood — Solubility of Sulphate of Barytes. 



The presidents of this section were successively MM. Leibig, Woehler, 

 Schoenbein, and Rose; under the former of whom, during the first 

 clay's session, the following communications, in the order here given, 

 were submitted : 



M. Schlossberger, Professor at the University of Tubingen. — The 

 province of this savant is animal chemistry, which is indebted to him 

 for numerous and interesting observations. His discourse on this 

 occasion related to the reagent of Schweitzer, the ammoniacal oxyd 

 of copper, which possesses the curious property of increasing the bulk 

 and dissolving both cellulose and silk. M. Schlossberger has ascer- 

 tained that the ammoniacal oxyd of nickel exerts, to a certain extent, 

 the same property with reference to silk as the reagent with a copper 

 base; only, in the case of the latter, the solution of the silk retains the 

 blue color, while it is of a yellowish brown when treated with the 

 nickel. 



The cupro-ammoniacal liquid dissolves neither gum nor dextrine, but 

 it readily dissolves the filtering paper. The salts, and more especially 

 the alkaline salts, precipitate ^iis solution of cellulose; the precipitate 

 offers no trace of organization or crystallization, its centesimal com- 

 position not appearing to differ from that of the cellulose. 



The same alkaline salts do not precipitate the solution of silk; hence 

 we have the elements of a process for separating silk from cotton. A 

 neater process, however, is based on the employment of the ammoni- 

 acal oxyd of nickel, which, as we have seen, dissolves the silk, but is 

 absolutely without action on the cellulose. 



The solution of cellulose is equally precipitated by alcohol, by a 

 concentrated solution of honey, of gum arabic, or of dextrine. Schweit- 



