March 21, 1901] 



NATURE 



491 



appearance of a specimen is to be most strongly deprecated , unless, 

 indeed, this has been deliberately undertaken for the express 

 purpose of demonstrating some particular structural feature ; 

 yet many collectors are in the habit of making their specimens 

 ** look pretty." The conchologist removes the periostracum 

 from his shells, treats them with acid or oil, and conceals any 

 imperfection by aid of a file ; the entomologist is said to be not 

 above patching a damaged insect with parts taken from another 

 specimen (not necessarily of the same species) ; and corals are 

 occasionally provided with artificial bases of plaster of Paris. 



The practice in vogue in many museums of mounting small 

 specimens upon tablets is an exceedingly bad one, since it 

 greatly restricts any critical examination ; moreover, the speci- 

 mens are liable to be injured by the cement used. 



Collecting a Representative Series of Specimens. — As has been 

 pointed out, scientific research necessitates the examination of 

 large series of specimens exactly representing the form as it 

 occurs at the particular station where the specimens were 

 ■collected. The field naturalist will most readily ensure that a 

 series shall conform to this condition by collecting every speci- 

 men of the form in question which is observed during a certain 

 period of work — five minutes, an hour, a month, according to 

 its abundance and variability. And, in order that small local 

 variations may be rendered evident, the area over which the 

 series is collected must be a small one. If now the whole 

 gathering thus obtained is kept intact and unmixed with speci- 

 mens collected on other occasions or at different stations, it may, 

 safely be regarded as fairly representing the species as it occurred 

 at that particular time and place ; and it will form a satisfac- 

 tory basis for comparison with similar series gathered elsewhere 

 and at other seasons. It will probably be urged that this system 

 of collecting is impracticable, as it will entail greater cabinet 

 space. Granted that it may necessitate the provision of more 

 storage room, but is not the usefulness of a collection the only 

 excuse for its formation ? And if more space is required it 

 must be provided. However, this objection is not nearly so 

 serious as might be imagined ; it is by no means necessary or 

 even desirable that enormous series of specimens should be 

 •displayed for exhibition in museum cases or cabinets ; all that is 

 required is that they should be stored in such a way as to be 

 easily accessible when wanted for study. Thus in most 

 cabinets much space is occupied by cotton-wool which could 

 readily be filled with specimens without in the least adding to 

 the bulk of the collection. In any case, whatever difficulties 

 may be encountered they will have to be overcome, as only 

 when large series of carefully localised specimens from numerous 

 stations are gathered together in our museums and private 

 ■collections will it be possible for any really scientific taxonomic 

 work to be accomplished. Until this material is available it is 

 useless to argue over rules of nomenclature and such like, as 

 no satisfactory answer can yet be given to the fundamental 

 ■question, " What is a species?" S. Pace. 



Variations of Atmospheric Electricity. 



I ENCLOSE a photograph of the tracings, recording the atmo- 

 spheric electricity disturbances from January 4 to February 15 

 inclusive. The records are obtained in the following manner : 

 Two antennae are used, one vertical 20 metres in length, its 

 lower extremity connected to coherer. The other, 47 metres 

 long, consisting of an ascending vertical portion of 20 metres, 

 also connected below with same pole of coherer, a horizontal 

 portion of 7 metres, and a descending vertical portion of 20 

 metres, the whole being the shape of an inverted U, going up 

 one side of house, across the top and down the other side. 

 These two antennae are carefully insulated. The other pole of 

 coherer is connected to earth, in this case to the bottom of a 

 <leep well. The coherer closes the circuit of a relay, which in 

 its turn closes the circuit of two electro-magnets, one of which 

 draws up the style and so records a stroke on the revolving 

 drum ; the other sets a clockwork apparatus in movement which 

 strikes coherer and so decoheres. I'he receiver is situated on 

 a hill, overlooking the neighbouring country. 



The disturbances seem at times to recur about the same time 

 on successive days, or sometimes after an interval of a day or two. 

 For instance, the first two on the 4th and the first two on the 

 •9th seem to have some connection. Again, the second pair on 

 the 9th seem identical with the first pair on the loth. 



Taking the central group on the 9th, loth, 12th, 14th, it 

 might be subdivided into two groups, commencing on the 9th 



NO. 1638, VOL. 63] 



with two in each group, reaching its maximum on the loth, 

 five and seven, and on the I2th reduced to one in each group, 

 finally, on the 14th, only one remaining in the stronger group, 

 that is the one with a maximum of seven. 



On February 13 there was one disturbance, on February 14 

 two, the first of which was at identically the same time as the 

 one of the previous day. It would be interesting to compare 

 the records of several receivers and see how far-reaching these 

 disturbances are, or whether they are purely local phenomena. 

 For this purpose two more receiving stations are shortly to be 

 fitted up in this department. During the period covered by 

 these records there have been no visible or audible signs of 

 thunderstorms, and on many occasions the sky was cloudless, 

 barometer high, thermometer low — 28° F. to 36° F. — during the 

 last eight days of February, when there could have been no 

 storms within several hundred miles. E. Pellew. 



Bellevue, Laroin, Pau, Basses Pyrenees, France. 



The Selborne Yew-tree. 



Gilbert White, in his "Antiquities of Selborne," Chap. 

 V. (Chandos Classics Edition) mentions a male yew growing in 

 the churchyard. He believed it to be some centuries old and 

 states its girth as 23 ft. This afternoon I have, with Mr. Lewis 

 Eynon, remeasured the trunk and find it to be 25 ft. 6 in. 

 The stem of this magnificent tree is squat and rather bulging, 

 and as White mentions its girth as something extraordinary, it 

 is to be presumed that his measurement was made at the point 

 of maximum diameter— about four feet from the ground. This 

 is the height at which our figure was obtained, and we tased 

 a steel tape taken right round without regarding irregularities 

 of surface. The increase in girth will be seen to correspond to 

 a radial growth of 47 in. in the 120 years or so since White's 

 time. I know not whether recent measurements of this tree 

 have been published, but the fact seems worthy of record. 



F. Southerden. 



75 Barry Road, Dulwich, S.E. March 16. 



INJURIOUS CONSTITUENTS IN POTABLE 

 SPIRITS. 



AN interesting communication is just to hand, by Sir 

 Lauder Brunton and Dr. TunniclifTe, upon " Certain 

 apparently injurious constituents of potable spirits.'' Its 

 appearance now is certainly opportune, since, whatever 

 else we may be interested in, alcoholic beverages are 

 certainly attracting a deal of public attention at the 

 present time. It is further, if not a relief, certainly a 

 change, to learn that something else in alcoholic drinks 

 besides arsenic and selenium may be the cause of mis- 

 chief, and their removal advantageous. Our rhentation 

 just now is rather apt to be over-arsenicated ; moreover, 

 from the point of the consumer, the impurities discussed 

 by these workers certainly seem to have one important 

 advantage over arsenic, in that they can be completely 

 removed — that is, removed to the satisfaction of the 

 chemist as well as to that of the pharmacologist. 



The subject of whiskey, with which the above mono- 

 graph is concerned almost entirely, has not received very 

 much attention at the hands of chemists, pharmacolo- 

 gists or dietetic experts, since the publication, in 1891, of 

 the report of the select Committee on British and Foreign 

 Spirits. This Committee directed itself mainly to the 

 question whether compulsory bonding, as practised in 

 Canada, should be adopted in this country, and also 

 whether any restrictions should be placed upon blending, 

 as by, for instance, limiting the name whiskey to the 

 product made from malt, or malt and grain, in a so- 

 called pot-still. The result of the Committee, so far as 

 legislation was concerned, was nil. In the course of the 

 inquiry, however, many interesting pharmacological facts 

 came out, and the present work must be looked upon 

 as a continuation of what may be termed the pharma- 

 cology of whiskey. Readers who are interested in the 

 subject are strongly recommended to consult the Blue 

 Book, which contains a mass of most interesting and 

 important information. 



