1 INTRODUCTION. 



Table 65. Millimetres into inches. 



From o to 400 mm. the argument is given to every millimetre, with 

 subsidiary interpolation tables for tenths and hundredths of a millimetre. 

 The tabular values are given to four decimals. From 400 to 1000 mm., 

 covering the numerical values which are of frequent use in meteorology 

 for the conversion of barometric readings from the metric to the English 

 barometer, the argument is given for every tenth of a millimetre, and the 

 tabular values to three decimals. 



Example : 



To convert 143.34 mm. to inches. 

 The table gives 



143 + -3 + -04 ™ni. — 5.6299 + 0.0118 + 0.0016 inches = 5.6433 inches. 



Table 66. Feet into metres. 



From the adopted value of the metre, 39.3700 inches — 

 I English foot = 0.3048006 metre. 



Table 66 gives the value in metres and thousandths (or millimetres) 

 for every foot from o to 99 feet ; the value to hundredths of a metre (or 

 centimetres) of every 10 feet from 100 to 4000 feet ; and the value to tenths 

 of a metre of every 10 feet from 4000 to 9090 feet. In using the latter 

 part, the first line of the table serves to interpolate for single feet. 



Example : 



To convert 47 feet 7 inches to metres. 47 feet 7 inches =47.583 feet. 

 The table gives . 47 feet = 14.326 metres. 



By moving the decimal point, 0-583 << == 0.178 



47.583 feet = 14.504 metres. 



Table 67. Metres i7ito feet. • 



I metre = 39.3700 inches = 3.280833 + feet. 



From o to 500 metres the argument is given for every unit, and the 

 tabular values to two decimals; from 500 to 5000 the argument is given to 

 every 10 metres, and the tabular values to one decimal. The conversion foi 

 tenths of a metre is added for convenience of interpolation. 



Example : 



Convert 4327 metres to feet. 

 The table gives 



(4320+ 7) metres = (14173.2 + 23.0) feet= 14196.2 feet. 



