282 



NA rURE 



[July 20, 189; 



knowledge, that such vast accumulations of what were origin- 

 ally highly fertilising substances should be discharged into the 

 estuary of the Thames, and not only be absolutely wasted, but 

 converted into a perpetual nuisance, brought up at each tide 

 within the limits of the metropolis from which they started. 



" It is true that within the last fifty years we have imported 

 enormous quantities of guano, phosphates, ond nitrates, but of 

 these there must eventually become a scarcity, if not an end. 

 In the meantime, may not chemists do something to reduce the 

 waste of feitilising agents that is now taking place among us? 

 Agricultural colleges have been founded — agricultural chemistry 

 is a recognised branch of science ; but with increase of know- 

 ledge has come increase of foreign competition, fostered by 

 improved means of transport and communication, and it is at 

 the present time a doubtful point whether many soils, even if 

 rent-free, can be cultivated in this country for cereals, except at 

 a loss. 



" While touching on agricultural chemistry, I cannot pass over 

 in silence the experiments which have now been carried on con- 

 tinuously for a period of fifty years at Rothamsted, by Sir John 

 B. Lawes, assisted during the whole half-century by Dr. Gilbert. 

 The extremely liberal provision which, during his life-time. Sir 

 John Lawes has made for the purpose of continuing and extend- 

 ing his experiments, would alone entitle him to a full measure 

 of public gratitude. When, however, we consider the nature 

 and extent of the experiments already conducted, we must feel 

 that no expression of public estimation can be too high when, 

 as will shortly be the case, the Rothamsted jubilee is celebrated. 

 As to the results already obtained, and as to the nature of the 

 experiments still being carried on, it would be out of place here 

 to enlarge. Remarkable, however, as are the effects of different 

 manures on the botanical character and growth of herbage, 

 and on the strength and yield of cereals, the different results 

 arising from the mere variation of the temperature, sunshine, 

 and rainfall, in successive years, are more remarkable still. 



" I feel, however, that I have detained you long enough with 

 these crude considerations of topics more or less chemical in 

 their character, and that it is time for me to conclude. 



" We are here assembled on the borders of the two counties 

 of Lancashire and Cheshire, in both of which are great centres 

 of chemical manufactures, and the principal productions of 

 which are in a great degree dependent on the knowledge and 

 due application of chemical laws. We meet at the seat of one 

 of the most active sections of the Society of Chemical Industry, 

 which has received us with open arms, and has provided us 

 with an 'Open Sesame,' which will admit us to inspect many 

 of the most interesting of the works and factories of the district. 

 We gladly avail ourselves of the opportunities thus liberally 

 opened to us, and if by chance any of us can afford assistance, 

 advice, or encouragement to our brethren in Liverpool, I am 

 sure that all present will gladly render it, and not forget that 

 we are all members of one body, and all mutually interested 

 in the advance of chemical knowledge, and especially of Chemical 

 Industry." 



THE PLAGUE OF FIELD VOLES. 



"D ATHER more than a year ago a Committee was appointed by 

 the Board of Agriculture to inquire into and report upon 

 the circumstances attending the existing plague of voles in some 

 of the southern counties of Scotland ; and to ascertain, either ex- 

 perimentally or otherwise, whether any, and if so what, pre- 

 ventive and remedial measures could be adopted, and under 

 what conditions those measures were likely to be of value. 



The committee consisted of Sir Herbert Eustace Maxwell, 

 Bart., M. P. (chairman), the Right Hon. the Earl of M into, K.T., 

 the Rev. John Gillespie, Prof. D'Arcy W. Thompson, and Mr. 

 Walter Elliot. 



Mr. J. E. Harting, Librarian of the Linnean Society, acted 

 as the Secretary to the Committee. 



From the recently-published report we obtain the following 

 information. "The animal, which by excessive multiplication has 

 caused so much mischief on hill-farms in the southern uplands 

 of Scotland, is the short-tailed field-vole {Arvicola agresiis). 

 At all seasons it is a well-known inhabitant of our pastures and 

 may be found at all heights from sea-level to near the summits of 

 our highest mountains. It usually produces three or four litters 

 a year, each consisting of from four to eight young, but in some 

 seasons they are even tnore prolific, the breeding season is pro- 



longed, young voles being observed from February to Novem- 

 ber, and the litters containing as many as ten young. 



" The present outbreak may be traced back to the year 1888, 

 when the voles were observed to be increasing on the farm of 

 Glenkerry and others in Selkirkshire. In the summer of 1889 

 the low-lying pastures near Closeburn, in Dumfriesshire, were 

 observed to be infested by enormous numbers of voles, which 

 remained there duiing 1890, and disappeared in 1S91, probably 

 moving up to the hill pastures, where in June 1892 they weie 

 swarming. 



" The districts principally affected are the hill pastures in the 

 north-west of Roxburghshire, the south of the counties of Sel- 

 kirk, Peebles, and Lanark, and the northern part of Dumfries 

 from Eskdalemuir by Moffat to Thornhill. The voles have also 

 appeared in great numbers in the parishes of Dairy and Cars- 

 phairn, in thestewartry of Kirkcudbright. 



" Mr. R. F. Dudge on has estimated that in Roxburghshire 

 30,000 to 40,cco acres had been affected, of which he considered 

 12, coo to 15,000 acres had been rendered useless ; in Dumfries- 

 shire 40,000 to 50,000 acre?, and in the stewartry of Kirkcud- 

 bright 10,000 to 12,000 acres were described by him as infested 

 by voles." 



" The map accompanying the report of the Committee shows 

 that an area not less than 6co miles in length and from 12 to 

 20 miles in breadth has been overrun. 



We reprint the following conclusions and recommendations 

 contained in the report. 



" The Committee have reluctantly been led to the conclusion 

 that they are unable to recommend any specific method of deal- 

 ing with or putting an end to the present outbreak. 



"It appears to be an instance of the power which small animals 

 are well known to possess, of prodigiously rapid multiplication 

 under favourable climatic conditions and with a plentiful supply 

 of natural food. 



"Experience shows that a combination of such favourable 

 conditions will always tend to bring about a recurrence of 

 the plague. That being so, it ought to be the endeavour of 

 eveiy farmer and shepherd to be on the alert, and report with- 

 out delay to the land agent, and to the secretary of the local 

 farmers' club, or agricultural society, the first signs of the multi- 

 plication of vermin, so that palliative measures may at once be 

 adopted, not on isolated farms, but everywhere throughout the 

 district. 



" The most effective measures appear to be periodical and 

 timely burning of grass and heather, followed by active pursuit 

 of the vermin by men using wooden spades and dogs. If this 

 were promptly done in the early stages of the outbreak, it is 

 quite possible that it might be averted altogether, or greatly 

 mitigated in severity. 



" It is hardly necessary to point out that the proprietor of the 

 land should be informed as soon as anyone else, because his 

 keepers and others might be usefully employed in assisting to 

 prevent what amounts, if unchecked, to a common calamity 

 upon all classes connected with land. 



"Where plantations of limited extent are attacked, pit-falls 

 wider at the bottom than at the top and about 18 inches deep 

 should be dug. The voles fall into them and cannot escape, 

 and the ground is soon cleared of them in this way. 



"The Committee cannot speak with approval of the use of 

 poisoned grain, except where the area affected is very limited. 



" Nor have they been able to come to any conclusion favourable 

 to the adoption of Prof. LoefHer's method of destroying voles 

 by means of bread saturated in a preparation of the bacillus 

 typhi murium, or mouse typhus. The personal investigations 

 made by the chairman and secretary in Thessaly (where in May 

 1892 Prof. Loeftler 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. 



"The Committee readily admit that, when used in a fresh state, 

 the bacilliferous fluid is an effective though somewhat dilatory 

 poison for mice and 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 Prof. Loeffler that the Scottish 

 voles sent to him alive by instructions from the Committee have 

 been found as susceptible of the mouse typhus bacillus as their 



NO. 1238, VOL. 48] 



