530 ON DRAUGHT. 



for our present purpose to show that there still exist great objections to 

 the universal application of machinery to draught, — objections which do 

 not equally apply to the use of animal power ; that there are many ad van - 

 tages in the latter, which are not yet obtained by the former ; and that 

 animal power continues, for all the ordinary purposes of traffic upon 

 common roads, to be the most simple in its application, and certain in its 

 effect. 



We shall confine ourselves particularly'' to the consideration of that part 

 of the question which relates to the slow transport of heavy goods, as being 

 the most important branch of the subject, especially for agricultural pur- 

 poses. Economy is, of course, the grand desideratum in the consideration 

 of this question ; consequently, the comparative expense of the two powers, 

 supposing them for the moment equally convenient and applicable, will 

 first demand ovu* attention. 



A difficulty arises here, however, from the want of a certain measure of 

 comparison. The power of a one-horse engine is by no means exactly the 

 same thing as that of a horse. As we have before stated, the mode of ap- 

 plying them being different, the variations in the results are different, and 

 consequently the effects do not bear a constant proportion to each other, 

 in diS'erent circumstances : we must therefore be careful not to fall into 

 the mistake which we have ourselves pointed out as a very common source 

 of error, viz., the drawing general conchisions fi-om data obtained in a par- 

 ticular case. We shall take the power of the horse, and that of the steam- 

 engine as ascertained practically on railways, where the effect of each is 

 less mfluenced by accidental circumstances, and consequently can be better 

 ascertained than on a road. We shall confine our calculations of expense 

 to this particular case, and then endeavour to discover how far the same 

 results are to be expected, or what modifications are likely to take place, 

 and what alterations are to be made in the results under different circum- 

 stances. As regards the first, viz., the comparative cost of animal and 

 mechanical power on a railway, we cannot do better than quote the words 

 of the late Mr. Tredgold upon this subject, and we accordingly extract the 

 following passage from his work upon Railways : — 



' The relative expense of different moving powers for railways is an 

 interesting enquiry, and the same materials being necessary to estimate the 

 absolute expense for any time or place, it is desirable to give some particu- 

 lars to aid the researches of those who wish to make such comparative 

 estimates. The annual expense of a horse depends on: — 



'1. The interest of purchase -money. 



' 2. Decrease of value. 



* 3. Hazard of loss, 

 ' 4. Value of food. 



' 5. Harness, shoeing, and farriery. 



' 6. Rent of stabling. 



' 7. Expense of attendance. 



* According to the average duration of a horse in a state fit for labour, 

 of the description required on a railway, the first three items may be es- 

 timated at one-fourth of the purchase-money ; the food, harness, shoeing, 

 &c., included in the 4th, 5th, and 6th, will most likely not exceed 401. per 

 annum, nor yet be much short of that amount ; and supposing one man to 

 attend to two horses, this would add 15?. 12.s. if the man's wages Avere 2s. 

 per day ; and, at this rate, the labour of a horse of the value of 201. would 

 cost 601. 12s. per year ; or, since there are 312 working days in the year, 

 the daily expense would be 35. lO^d., or 186 farthings. But the power of 

 a horse is about 125 lbs. when travelling at the rate of three miles per hour, 

 and the day's work eighteen miles. 



