viii PREFACE 



practical man the weights and measures to which he 

 is accustomed this has been done. In any case the 

 relation between the two systems hardly requires 

 a greater knowledge than that i kilogram (kg.) = 

 2-2 Ibs. ; I litre = if pints ; i oz. = 28 grms. (g.). 



W, GOODWIN. 



SOUTH-EASTERN AGRICULTURAL COLLEGE, 

 WYE, KENT. 



