Mr. Shepard's reply to Prof. Del Rio. 



313 



Characteristic of Breithavpt. 



Without saline, alkaline, and sweet 

 tasted, or aqueous cooling, solu- 

 bility on the tongue.* 



When H. 0-25... 4-0, which 

 is not the case with the 

 nmineral sought. 

 When H. 4-0... 5-75, which 

 is not the case with the 

 mineral sought. 

 When H. 5-75 . . . 8-75 and 

 G. from 2-0 .. . 4-0, ex- 

 cept such as have G. 3'5 

 and more, but the mineral 

 sought has G. above 3*5; 

 it is therefore excluded 

 from Class II. 

 III. Class. Minerals. 

 All those with metallic lustre and 

 G. from 3-2 ... 22-0 belong 

 here without exception. 

 Those with common lustre, having 

 H. from 0-50 . . . 9;0 and G. 

 from 2-2 ... 8-5 belong here 

 under the following conditions ; 

 If H. 0-50 . . . 2-50, which 

 is not the case with the 

 mineral sought. 

 IfH. 2-50 ...6-0, which is 

 not the case with the min- 

 eral sought. 

 If H. 6-0 .. . 7-0, which is 

 not the case with the min- 

 eral sought. 

 If H. 7-0 ... 90; and G. 

 3'9 . . . 8"5, which proves 

 the mineral sought to fall 

 within the present class. 



My Characteristic. 



If the mineral sought is massive 

 and easily cleavable, it is to be 

 sought in this class. 



III. Class. UncrystalUzed 

 Minerals, (i. e. massive miner- 

 als, not yielding cleavage forms.) 



If the mineral sought is massive 

 and uncleavable, it falls within 

 this class. 



♦ Prof. Del Rio's translation is, '.soluble on the tongue without .salty, alkaline 

 and sweet taste.' The German is, ' ohne salzig, al/calisch und susslich schvieckerf 

 de aiich ohne vOasrig kaltcnde aujlodichkeit nii.f der Zunge.' 



Vol. XXVII.— No. 2. 40 



