500 
south-western part of the continent in the neighbour- 
hood of Cape Town; it amounts to an increase of 
southerly dip of 8’ a year. The line of no change 
passes through Madagascar; east of that there is a 
decrease of southerly dip. The annual change in the 
horizontal intensity shows a decrease in absolute mag- 
nitude towards the north; over the greater part of the 
Union it has a value of from 80 y to 100 y yearly, and 
is a decrease. 
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Historical Account of Ghee Cross Hospital and 
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County Borough of Halifax. Bankfield Museum 
Notes. Second series. No. 4. Coptic Cloths. By 
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2S. OG. 
Memoirs of the Geological Survey. England and 
Wales. The Water Supply of Nottinghamshire from 
Underground Sources. By G. W. Lamplugh and B. 
NO! 2332, VOL. 93] 
NATURE 
[Jury 9, 1914 
(London: H. 
Smith. + Pp. 
Office.) 5s. 
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107. (London: H.M, Stationery Office.) ts. 
iv+174. M. mee vite 
CONTENTS. PAGE 
History and Philosophy of Mathematics ... . 475 
Precursors of Christianity. By A. E. Crawley. . 476 
Haberlandt’s Plant Anatomy. Pade BaP.) < %s) oeeeeay 
Electrotechnics . 4 :-5.5 asec é ay fea apt is: ape AR 
Our Bookshelf £5 een 2 ee aS 
Letters to the Editor :— 5 
Active Nitrogen.—Prof. H. B. Baker, F.R.S., 
Dr. Erich Tiede, Hon. R. J. Strutt, F.R.S., 
Emil Domcke 
The Horns of the Okapi.—R. Lydekker, F. R. s. . 478 
Thorium Lead-—-An Unstable Product.—Robert W. 
awson..) a tepiey iy eine besiel fe neal ae en 479 
Radio-activity and Atomic Numbers —Dr. A. van 
den,Broek . ./\):-e See eae eee 480 
Seeing and Photoerpeane ety, Fainly Illuminated 
@bjects. — Prof. P= Ga Nuttinigssssce) /eee 480 
June Meteors.—W. F. Denning. .... . -. 480 
Inorganic ‘‘ Feeding.” (Z¢/zestrated.)— 2 Ghas’ Re 
Dy ae . PPh ie fied BANar OR SS 481 
Experimental Demonsenaide of an Ampere Mole- 
cular Current in a Nearly Perfect Conductor .. 481 
Memorial Statue of Capt. Cook. (///ustrated.) . . . 481 
The Wilds of New Zealand. (J//lustrated.). .. . . 482 
Recent Progress of the Metric System .. . pare isi 
INOtCS 02%). °2 |... (8) 2 ee eee re . eS Gee On 
Our Astronomical Golacint — j 
A Faint New Comet (19140) 2 5s 2. 4 2G . » thes 
Opposition-of- Eros (433) this Year..°. ... . .. 14. 488 
Recent Publications of the Allegheny Observatory... 488 
The Variable Satellites of Jupiter and Saturn. . . . 489 
Third International Congress of Tropical Agri- 
GUIPETe™. 5 \S » : ee eee 489 
International Gommiasion for Scientific. Radios 
telesraphic, Researches as een ane - 490 
The Research Defence Society .. . 491 
The Synthetic Power of Protoplasm. "By E. F, We 49t 
Piaeanspiration iin Plantssc a eee eee 2 eAOe 
The American Philosophical Society ....... 492. 
X-Rays and Crystalline Structure. By Prof. W. H. 
Brace; F.RS.... 5. i cae ences el ae 494 
University and Educational Intelligence. . . . . . 498 
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