216 On the American Mineral, Lancasterite. 
will ere long, among other improvements in the music of our 
churches, demand that it be given in pure harmony, and in ac- 
cordance with the fixed and demonstrable principles of music. 
That music may be investigated with something of the same 
learning and research which is bestowed upon almost every other 
science, isan end much to be desired. It will be gratifying to 
the writer—even if some of his opinions are shown to be incor- 
rect—if his labors in this department of science, shall have the 
effect of calling to this subject the attention of those who are bet- 
ter qualified to make further investigations, and who can lay them 
before the public in a more interesting manner. 
Note.—In the music example in (18.) page 77, the second 
lower note in the base clef, should be Bb instead of D; and the 
also should have been placed on the second, instead of the third 
line. We would here also state that this and several other music 
examples in this paper were intended as theoretical illustrations, 
rather than as examples for actual execution. 
Art. XXIIL—On the new American Mineral, Lancasteriie ; 
by Prof. B. Sittiman, Jr. | 
Amone the minerals associated with the Serpentine of Texas, 
Lancaster Co., Pennsylvania, received through the kindness of 
Mr. L. White Williams of Westchester, one has close resemblance 
to Brucite. On chemical examination it has proved to. be a new 
hydrous carbonate of magnesia, for which I propose the name 
Lancasterite. The following are its characters :— 
_ Foliated like Brucite, affording thin pearly lamine, inelastic 
and somewhat flexible. Also small crystals, which appear to be 
monoclinic (?) with an eminent pearly diagonal cleavage, H=2'9. 
G =2-33 according to my determinations; 2°35, according to H. 
Erni. Translucent. According to two analyses by H. Erni, it 
contains, 
1. 2. Mean. Oxygen. 
Carbonic acid, 27-07 2685 26:96 19-61 
Magnesia, 001 ©5072 5036 19°79 
Protoxyd of iron, 1-01 0:96 0-99 0-21 : 
Water, 21-60 
99:69 100-00 
This gives the formula Mg 6+Mg H? = carbonic acid 27-11, 
magnesia 50-78, water 22°11=100. In two other trials the # 
and 6 together equaled 49-83 and 49°86 after 14 days drying 1 
the water bath. Ina matrass the mineral yields much water. 
