ETE er er a 
id : 7 
CONTENTS OF VOLUME Ix. 
NUMBER XXV. 
Page. 
Art. I. Experiments on the Electricity of a Plate of Zinc buried 
in the Earth; by Prof. Extas ss - - 
II. Geology of aids, : iy eee 3 
III. Ash Analyses; by Jno. A. Poses ee 20 
IV. A Product of the action of Nitric Acid on Woody ‘Fibre; ; 
by Jno. A. Porter, - 
V. On the Navicula Spencerii ; by Winiite De LA Re, - 23 
VI. Caricography ; by Prof. C. Dewey, - 
VII. On a wees of Iron and some other Nitrates ; by i OHN M. 
Orp 
Vil. & ones of two additional Crags of tie Sit-enky 
(Troglodytes gorilla, er from — — by 
Jerrries Wyman, M.D., « es 
IX. Notice of the cranium of the Nessie! a new species of 
Manatee (Manatus nasutus) from W. Africa ; - JEFFRIES 
Wyman, M.D., - - - - 45 
X. On Denudation in the Pacific ; é py D. Dak - - 48 
XI. Remarks on the Constitution of Leucine, with habits! observa- 
tions upon the late Researches of M. Wutz; by T. S. Hunt, 63 
XII. On Perfect Musical Intonation, and the fundamental Laws 
of Music on which it depends, with remarks showing the 
practicability of attaining this Perfect Intonation in the Or- 
an; by Henry Warp Poors, ns 
XIII. Analyses of several Minerals; by Wine Pinions - 
XIV. Memorials of John Bartram and Humphry Marshall, with 
notices of their Botanical. — 7” Wm. Dar- 
Lineton, M.D., LL.D., 85 
XV. Vibrations of Dieeniyhs's bail by ‘he Galvanic Curtin, 
by Prof. Cuas. G, Pace, : 
XVI. On four new species of are of ae genus Ploiaria, 
Chermes, and Aleurodes, and two new Hymoncne'ys para-- 
sitic in the last named genus; by S. S. Hatpeman, - 108 
