Dr. Atkinson's Chemical Notices from Foreign Journals. 197 



be a constant one in tlie Paisberg crystals; the face s is frequently, 

 as well as m, a predominant one : — 



mt = 87 20 

 tp = 86 10 

 mp =110 40* 

 me =136 20 

 my' = lS8 20 

 7ns =148 42 

 mc = 86 35 

 tc =142 30 



Cleavage highly perfect, parallel to m andp, less so to t. From 

 this it would appear that rhodonite, or manganspath, belongs to 

 the anorthic system, having, as W. Phillips described it, a doubly 

 oblique prism for its primary; it cannot therefore be isomor- 

 phous wdth augite, though having a similar formula. That rhodo- 

 nite has any regular cleavage giving an angle of 90°, appears to 

 me to be very problematical ; the figure and angles I have now 

 given may, however, afford some key or explanation to the various 

 and discordant descriptions hitherto published respecting the 

 form and cleavages of this mineral. 



XXV. Chemical Notices from Foreign Journals. 

 By E. Atkinson, Ph.D. 



[Under this title it is proposed to give, from time to time, 

 abstracts of the more important chemical contributions to the 

 foreign scientific journals. The chemist will not find in them a 

 substitute for the use of the original memoirs or their transla- 

 tions, as they will merely give the final results, and not detailed 

 descriptions of the processes. Their object is to afford to the 

 general scientific reader an idea of the progress and direction of 

 the labours of foreign chemists.] 



LIEBIG'S Annalen der Chemie und Pharmacie for September 

 contains two important papers by Liebig. The first of 

 these is " On the Constitution of the Compounds of Mellone.'' 

 The author's formula for these compounds had been called in 

 question by Gerhardt, who assumed in them a radical hydro- 

 mcllone. Liebig's earlier formrda for the mellone metals was 



* This angle a])pears to vary slightly measured on cleavage faces, viz. from 

 110° .W to 11 2° 30', W.Phillips giving 11 2° 30'; the crystalline variety from 

 Paisberg, 110' 30' to IIP 0'; and that from Franklin, New Jersey (show- 

 ing also occasionally the faces m, e, t) 11 1° 30'. 



