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Publications of 
Carnegie Institution of Washington 
The publications of the Institution now number over 350 
volumes, the subjects including Anatomy, Archology, As- 
tronomy, Botany, Chemistry, Economics and Sociology, Em- 
bryology, Experimental Evolution and Heredity, Engineering, 
Folk-Lore, Geology, History, International Law, Literature, 
Mathematics, Medicine, Nutrition, Philology, Physics, Zoology. 
Classified and descriptive lists will be sent postpaid on appli- 
cation. 
No. 78._ SHaw, J. B. Synopsis of Linear Associative Algebra: 
Report on its Natural Development and the Results 
Reached up to the Present Time. Quarto, 145 pages. 
Price, $1.50. 
No. 120. Drcxer, F. F. The Symmetric Function Tables 
of the Fifteenthic. Quaito, 21 pages. Price, $1.25. 
No. 105. Leumer, D. N. Factor Table for the First Ten 
Millions, containing the smallest factor of every number 
not divisible by 2, 3, 5, or 7 between the limits 0 and 
10017000. Folio, xiv-+476 pages. Bound in Leather and 
Buckram. $20.00; Unbound, $18.00. 
No. 165. Lexumer, D.N. List of Prime Numbers from 1 to 
10006721. Folio. xvi+133 pages. Price, $5.00. 
RECENTLY ISSUED 
No. 245. Hepricx, H.B. Interpolation Tables or Tables of 
Proportional Parts, containing the Products of the nearest 
unit of all numbers from 1 to 100 by each hundredth 
from 0.01 to 0.99 and of all numbers from 1 to 1000 by 
each thousandth from 0.001 to 0.999. Folio. 149 pages. 
Price, $5.00. Sila 
IN PRESS” 
No. 256. Dickson, L.E. History of the Theory of Numbers. 
Octavo. Vol. I. Divisibility and Primality. In press. 
All communications should be addressed to 
CARNEGIE INSTITUTION OF WASHINGTON 
WASHINGTON, D. C. 
In treatment synthetic rather than algebraic 
Lehmer’s Elementary Course in 
Synthetic Projective Geometry 
gives the student a wide outlook, a familiarity 
with many theorems useful in later work, and 
a certain power of visualization valuable in 
analytical studies. ‘‘Synthetic Projective 
Geometry’’ is peculiarly fitted for short 
courses. It can be given to the average fresh- 
man class in three hours a week through one 
semester. It may, however, be easily ad- 
justed to longer courses, if desired. The 
course includes correspondences, point rows 
and pencils of the first and second order, 
Pascal’s and Brianchon’s theorems, duality, 
poles and polars, involution, metrical develop- 
ment, and a chapter on the history of the 
subject. 
xiii +123 pages. $1.12 
Ginn and Company 
Boston Atlanta 
New York Dallas 
Chicago Columbus 
London San Francisco 
The University of California Press 
Berkeley, California 280 Madison Avenue, New York 
SOME TESTS OF DOUGLAS FIR 
AFTER LONG USE 
By Arthur C. Alvarez..........:..-c-sceeeeeeeeeeee .70 
The Strength of Long-Seasoned Douglas Fir and Red- 
wood, by Arthur C. Alvared........::.ccccscceesstteeseeneeeeeens 10 
Some Compression Tests of Portland Cement Mortars and 
Concrete Containing Various Percentage of Silt, by 
Arthur C. Alvarez and James R. Shields .................. 25 
The Wintun Hesi Ceremony, by S. A. Barrett............... -50 
New Pacific Coast Marine Algae LII, by Nathaniel Lyon 
Gardner. to aerepiasracken 35, 
New Pacific Coast Marine Algae IV, by Nathaniel Lyon 
(Geis BE a ae rapeeaceercocoR MELE Se OO dSSt oS eA EECCA DS SEEN ESCO E ECE 10 
The above titles represent University of California Publications 
in Engineering, Anthropology and Botany. Other series 
published by the University of California include Agricultural 
Sciences, Entomology, Geography, Geology, Pathology, 
Physiology, Psychology, and Zoology. 
Complete Usts of titles and prices wili;be sent 
on request} 
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