2:i2 THE AMERICAN MOXTlllA [Aug. 



The Isc of Rullicniuui Red in IMant Hislolojry. 



TranslalCil ami Cotulcuscil, 

 \W A. H. ATHHRT, 



OUtiXt). MK. 



At thr meeting of Deeember '2(>tli, 1S92, of tho FnMich Acad-, 

 emv of Sciences, Mr. A.Joly presented a pajiiT upon the ani- 

 nioniacal compounds ofthesesquichloride of ruthcniuni. Among 

 these compounds isrRuj (OH)- (M., (NMI;, )- 3 IT.. Owliicli 

 is formed l»y adtling very linely divided anhydrous ses(|uiclilo- 

 ride of ruthenium to a cold solution of ammonia. Iftliis be 

 kept at a tenijierature of4(»° for soni(> time the liipiid becomes 

 deep red and when sufficiently concentrated small brown crys- 

 tals of the above formula separate out. The solution of this 

 ctmipound is red, seen by transparence, but of a violet hue when 

 viewed by reflection. It has such strong tinctorial powers that 

 it may fitly be compared with the organic dyes. 



At the meeting of March 20th, 1893, Mr. L. Mangin, i)resented 

 a pai)er upon the ai»i)lication of this ruthenium red or oxychlo- 

 ride of ruthenium to vegetable histology. 



He says that from it.s chemical com])osition and behavior with 

 acids and alkalies it must be looked Ujton as a basic stain char- 

 acterized by its inertness as regards cellulosic compounds and 

 its power of staining pectic compounds with varying degrees of 

 intensity. 



The stain is not decolorized by alcohol or glycerine and sec- 

 tions stained with it may be dehydrated and mounted in Canada 

 Balsam. It fixes itself energetically upon mucilage derived 

 from pectic compounds, but does not stain that derived from cel- 

 lulose. 



The introgenous compounds in plants are unequally stained 

 and always with less energy than ]»ectic derivatives ; the nucleus 

 and granular protojtlasm stain with varying intensity, the ])roto- 

 plasm staining but slightly. The above results refer more par- 

 ticularly to fresh tissue ]»reserved in alcohol. By treating the 

 sections wiih alum or neutral acetate of lead the aflfinity of the 

 nucleus and protoplasm for the stain become more energetic. 



To take aniline stain out of cloth. --Dissolve one i)art of 

 Sodium Nitrate in two i»arts of dilute sulphuric acid and 75 

 part** of distilled water. Let it stiind ov(-r night. Apply gently 

 and rinse carefully. 



