REPORT ON PLAGUE OF FIELD-VOLES IN SCOTLAND 143 



of the bacillus typhi murium, or mouse typhus. The personal 

 investigations made by the chairman and secretary in Thessaly 

 (where in May 1892 Professor Loeffler was employed at the 

 expense of the Greek Government to combat the plague of 

 field-voles then prevailing in that country) convinced them 

 that the favourable reports circulated as to the complete 

 success of the experiments have not been justified by the 

 results. In certain parts of Thessaly the voles were reported 

 by landowners and others to be as numerous in January 1893 

 as ever they were. 



Your Committee readily admit that when used in a fresh 

 state, the bacilliferous fluid is an effective though somewhat 

 dilatory poison for mice or voles, and has this advantage 

 over mineral poisons that, as has been proved, it is innocuous 

 to human and other forms of life. 



It has also been reported by Professor Loeffler that the 

 Scottish voles sent to him alive by instructions from your 

 Committee have been found as susceptible of the mouse 

 typhus bacillus as their Greek congeners. But there are 

 three objections which in the opinion of your Committee 

 render this method almost worthless except for employment 

 in houses, gardens, enclosed fields; or other limited areas : 



1. It is very expensive ; the virus supplied to the Greek 



Government was paid for at the rate of about 4s. a 

 tube, containing enough when dissolved to treat 

 about two imperial acres, a cost which in many 

 instances would exceed the rent of the Scottish hill 

 pasture. To this must be added the price of bread 

 used in distributing the virus, which would appreci- 

 ably raise the cost of the process. Thus to deal 

 effectually with a hill farm of say 6000 acres, would 

 entail an expenditure of from £yoo to ;£iooo, 

 making the remedy more costly than the evil. 



2. Mouse typhus is not contagious ; it can only be com- 



municated to those animals that will swallow some 

 of the virus. The allegation that healthy voles 

 will become infected by devouring the bodies of the 

 dead has not been satisfactorily proved. That 

 Greek voles when in captivity had been observed 



