FARM VERiMIN, HELPFUL AKD HURTFUL. 



CHAPTER 1. 



VOLES. 



For what sum would you undertake to keep a mouse 

 for a twelvemonth ? " was a question propounded to me by 

 a Scottish sheep-farmer in the summer of 1892, to which I 

 replied that I had never made the necessary calculation. 

 My interlocutor held about 6,500 acres of hill pasture in 

 Eskdale Muir, part of that tract stretching for sixty miles 

 between Hawick on the east and Newton Stewart on the 

 west, which was devastated by a visitation of voles during 

 1891 and 1892. ^' Would you do it for twopence?" he 

 asked. No, I certainly would not ; a mouse would surely 

 consume more than twopennyworth of food in the course 

 of a year. ^'Well," he continued, '^I reckon that I have 

 " 3,000,000 mice on my land " (this did not strike me as an 

 over-estimate, for we had seen the voles on the ground in 

 such numbers as to be like the pattern on a carpet) — 



3,000,000, and they have been there for two years. I put 

 down the damage done at twopence a head, and you have 

 admitted that this is not a high estimate." 



It took but a simple calculation to make out that 3,000,000 

 voles at twopence per head per annum would cost in two 

 years ;^SOj00o — a sum far exceeding the purchase-value of 

 the land. It was obvious, therefore, that the loss had been 

 over-estimated, and an attempt was made to arrive at a just 



B 



