WIND TABLES. xlV 



Example: — ai 



tan a = —^^ ' 

 -27 



Table 49 gives 90° — a = 32° 



a^S 58° JV. 



Note. — If the numerator and denominator both exceed 150 or if either exceeds 

 200, the fraction must be divided by some number which will bring them within the 

 limits of the table. The larger the values, provided they are within these limits, the 



easier and more accurate will be the computation. For example, let tan a = ^. 



The top argument is not given for 18, but if we multiply by 5 or 10 and obtain — — or 



. the table gives, without interpolation, 90° — a = 38° and a = W 52" IV. 



140 



CONVERSION OP VELOCITIES. 



TABLE 50. 



Table 50. Synoptic conversion of velocities. 



This table*, contained on a single page, converts miles per hour into 

 metres per second, feet per second and kilometres per hour. The argu- 

 ment, miles per hour, is given for every half unit from o to 78. Tabular 

 values are given to one decimal. For the rapid interconversion of velocities, 

 when extreme precision is not required, this table has proved of marked 

 convenience and utility. 



TABLE 51. 



Table 51. Conversion of miles per hour into feet per second. 



The argument is given for every unit up to 149 and the tabular values 

 are given to one decimal. 



TABLE 52. 



Table 52. Conversion of feet per second i^ito miles per hour. 



The argument is given for every unit up to 199 and the tabular values 

 are given to one decimal. 



TABLE 53. 



Table 53. Conversion of metres per second into miles per hotir. 



The argument is given for every tenth of a metre per second up to 

 60 metres per second, and the tabular values are given to one decimal. 



TABLE 54.. 



Table 54. Conversion of miles per hour into metres per second. 



The argument is given for every unit up to 149, and the tabular values 

 are given to two decimals. 



* From Hand-book of Meteorological Tables. By H. A. Hazen. Washington, 1888. 

 With permission of the author. 



