72 PRIMARY RESULTS 



grease, licence, insurance, and the depreciation on the 

 paraffin cistern (calculated at 10 per cent, of its cost). 

 The total cost under this head has been distributed over the 

 various operations performed by the machine on the basis 

 of fuel consumption, the assumption made being that there 

 must be some fairly close relation between the cost of the 

 fuel required for any piece of work, and the destructive 

 effect. Repairs and replacements to tractor implements, 

 &c., have been eliminated from the general repairs account, 

 and have been taken direct to the particular operation 

 concerned, in addition to the apportionment of the general 

 items. Thus, the charge of 17 6s. 9cZ. against ' Ploughing ' 

 includes the share of the general repairs apportioned on 

 a paraffin basis plus the cost of repairs and replacements 

 to the tractor plough ; the items 1 Is. Wd., 16s. 7cZ., and 

 2 Os. lOd. charged for repairs against the operations of 

 1 chaff-cutting ', ' grinding ', and ' sawing ' respectively 

 include an apportionment of the general item on the same 

 basis plus depreciation on belting, and so on for the remainder 

 of the various operations. 



The ' Depreciation ' on the machine is calculated on 

 a life of five years, that is 82 per annum in this case. 

 There are obvious objections to this basis, for depreciation 

 should depend on the amount of work done rather than 

 on the passage of time, but the work done varies so much 

 in its destructive effect, as, for example, in the case of road 

 haulage on the one hand, and chaff-cutting on the other, 

 that no satisfactory method of distribution along this 

 line.'alone suggests itself. Moreover, in an industry so 

 much in its infancy as the manufacture of agricultural 

 motors, the element of time cannot altogether be ignored, 

 for it is probable that the patterns of machines now in use 

 will have been superseded entirely during the next few years. 

 In distributing depreciation over the various operations 

 performed the same assumption has been made as in the 

 case of repairs, namely that the wear and tear should be 

 roughly proportionate to the fuel consumption, and thus the 

 paraffin used has been made the basis of the apportionment. 



