54 C. U. Shepard—Mineralogical Notices, 
e transverse electromotive force in iron is opposite in 
direction to that in gold. According to the theory proposed, 
therefore, an iron wire bearing a current should move across 
the lines of magnetic force in a direction contrary to that 
followed by wires of other materials, which it does not do. 
In view of these difficulties, it seems hardly possible at 
resent to accept Prof. Boltzman’s method of calculating the 
velocity of electricity. 
nyone desiring to see Prof. Boltzman’s note will find a 
translation of the same in the Philosophical Magazine of April, 
1880, p. 308. A rather confusing inaccuracy in translation is, 
however, to be found about the middle of page 308 in the 
sentence, “ Hence, if the force above denoted by K atself acts 
upon, ete.” This should read, ‘Hence, if the force above 
denoted by K acts upon the movable electricity ztse/f in the 
gold leaf, etc.” The position of the pronoun is here a matter 
of considerable importance, as anyone will see who reads Prof. 
ltzman’s note with care. 
Art. VII.—WMineralogical Notices; by CHARLES UPHAM SHEP- 
ARD, Emeritus Professor of Natural History in Amherst 
College. 
1, A peculiar mineral of the Scapolite family. 
THE substance here described was sent to me by that zealous 
mineralogist, Mr. John G. Miller, of East Templeton, Ottawa 
quadrangular, though in the larger individuals they are octangu- 
i Their length is 
the smallest are rarely below one-eighth of this size. They 
preserve the same diameter throughout their length, with the 
exception of a single example, where one of the larger size, 
shows a tendency to a regular acumination. The length of 
this crystal is 33 inches, its diameter at the larger extremity 
