Periodical Literature 



337 



The air circulates better and the plants survive when, other- 

 wise, they would succumb to the heat. 



Bulletin de la Station de Recherches Forestieres du Nord de I'Afrique, 

 December 30, 1915, pp. 113-4. 



MENSURATION, FINANCE AND MANAGEMENT 



Dr. Hemman describes a hypsometer, 



constructed by Dr. Wimmenauer in 1868, 



and reports on a series of tests in which 



Christen's, Wimmenauer's old, and the 



same inventor's sextant hypsometer were used. Christen's 



hypsometer is generally the most favored, and is in most cases satis- 



18G8 



Precision 

 Hypsometer 



^ 



