1V CONTENTS. 
Number 296. 
Page 
Arr. VIII.—The Earth a Magnetic Shell; by F. H. Biez- 
IX.—Note on the occurrence of Leadhillite Pseudomorphs 
at Granby, Mo.; by *W. MM. Voomm Eales S322 ee ae 99 
X.—The Precipitation and Gravimetric Determination of 
Carbon Dioxide; by F. A. Goocu and I. K. Purrps.- 101 
XI.—Velocity of Electric Waves; by J. Trowsriper and 
W:. Duane, (With Rlate 11) oso aS 104 
XII.—Distribution and the Secular Variation of Terrestrial 
Magnetism, No. 1; by L. A. BavEr.__-.---- EE 109 
XIII.—Complementary Rocks and Radial Dikes; by L. v. 
PIRSSON 2. soa Ue oe Bee eee ee ee rs 
XIV.—Mineralogical Notes; by W. H. Hopps .---.--.-.-. 121 
XV.—Calaverite from Cripple Creek, Colorado; by W. F. 
HILLEBRAND 4 Jelacpeies )i 2 eee EE Sa eee 128 
XVI.— Notes on Convenient Forms of Laboratory Apparatus ; 
by DecA. Kenwue tote oe. 25ers ee ee 
XVII.—Contributions from the Gray Herbarium of Harvard 
University, New Series, No. IX; by B. L. Rosrynson 
and J. Mi GREEnaran !9saeee> bo ceeeanae te eee 135 
XVIII.—Thomas Henry Huxley; by O. C. Marsp_---.--- ihe 
XIX.—Daniel Cady Eaton; by W. H. BreweEr----------- 184 
HRRATUM. 
In the paper by M. Carey Lea on the Color relations of atoms, ions and 
molecules published in the May number of this Journal, by an unfortunate mis- 
take on the part of the printer, the groups in the table on page 362 have been 
transposed so that groups three and four take the place of groups five and six 
and conversely. On page 361 the groups appear in their proper order. 
