^.ept. 26, 1889] 



NATURE 



535 



1779. Alliyrium alpestre, Milde. Now very rare in Clova 

 Mountains, and mostly in accessible places (G. A. P.). 



1781. Cetciach officinarum, Desv. Almost extirpated from 

 Orchard-town Tower, Kiikcudbrightshire, by fern-hunters 

 (J. M. A.). Used to grow on the walls of Drumlanrig Castle, 

 one of the seats of the Duke of Buccleuch, Dumfriesshire, but 

 not now found there (T. A. ). 



1782. Scolopendrinvi vul,^arc, Symons. Almost extirpated 

 from several places in Kirkcudbriglitshire by fern-hunters 

 (J. M. A.). Extirpated from several places in the vicinity of 

 Dumfries (J. W. ) On the burns falling into Loch Ness there is 

 now only one in which this plant is to be found, owing to the 

 ravages of the itinerant fern-colleclor referred to under 1772. 

 It still exists, however, in inaccessible stations (Gr. ). 



1783. IVooihiailvcnsis, R. Br. Well-nigh extirpated by fern- 

 hunters from the Moffat district (J. W.). 



1787. Cystopteris montana. This plant, though not at 

 present really uncommon round Aherfeldy, will not improbably 

 be made very scarce by fern-collectors. It has disappeared 

 altogether from one of the stations in which it was first found in 

 Britain (F. B. W.). 



1788. Polysliclmtn Loncliitis, Roth. Almost extinct on Meal- 

 fourvouny Mountain, Inverness-shire, through the action of 

 fern-collectors, and especially of the one referred to under 1772 

 and 1782 (Gr. ). Has been cleared from the Raven's Rock, near 

 Strathpeffer, Dingwall, Ross-shire, by summer visitors (T. A.). 

 Was plentiful near Castleton, Braemar, formerly, but the guides 

 learned that they could sell it at a shilling a plant, and it is 

 now difficult to get (T. A.). 



1803. Pkrgopteris {Polypodiiini) Robertiana, A. Br. ; Poly- 

 podium calcareum, Sm. Once abundant in the debris of an old 

 limestone quart y near Aberfeldy, but now nearly eradicated. 

 Fern-hunting visitors and tourists are largely to blame for this, 

 but the destruction has been completed by persons who collect 

 ferns for sale. That the species is not altogether lost in the 

 district is, however, shown by the fact that a few weeks ago a 

 local fern-hunter was offering plants for sale, and at the same 

 time plants of 1787, Cystopteris montana (F. B. W., July, 

 1887). 



1806. Osmunda regahs, L. Has disappeared from Ballin- 

 gear Glen, New Galloway, and from other places, as Colvend, 

 through the ravages of fern-hunters (J. M. A.). Extirpated 

 from several localities in the vicinity of Dumfries (J. W. ). Has 

 entirely disappeared from Loch of Park, and nearly from the 

 cliffs south of Aberdeen, in both of which localities it was 

 formerly plentiful. Fern-collectors are mainly responsible 

 (J. W. H. T.). 



1809. Botrychium Litnaria, Sw. Formerly very local in the 

 Pentlands ; now extirpated (G. A. P.). 



1818. Equisettim hyemale, L. Extinct in Mid-Aberdeen 

 (J. M.). 



Report of the Committee appointed for the purpose of co-operat- 

 ing with the Scottish Meteorological Society in making Afeteoro- 

 logical Observations on Ben Net'is. Mr. Btichan, Secretary. 



The work of carrying on the observations hourly, by night 

 as well as day, has been carried on by Mr. Omond and his 

 assistants during the year with the same enthusiasm and un- 

 broken continuity as in time past ; and the five daily observa- 

 tions in connection with the Ben Nevis Observatory have been 

 made at Fort William by Mr. Livingston with the greatest 

 regularity and care. 



As in the previous year, the state of the health of the ob- 

 servers, occasioned by their continuous residence at the top of 

 the mountain, where exercise in the open air is practically im- 

 possible during the greater part of the year, rendered it again 

 necessary to give them relief during the winter and spring. The 

 services of Mr. Drysdale were again secured for six months ; 

 Mr. R. C. Mossman, the Society's observer for Edinburgh, gave 

 his services as observer for six weeks in April and May ; and 

 Mr. McDonald, Edinburgh, has given a month's service as ob- 

 server in July and August of this year. Messrs. Omond and 

 Rankin, during the time they were relieved from the work of 

 the Observatory, took part in the work of the office of the 

 Scottish Meteorological Society, and gave material assistance, 

 more particularly in the reduction, preparation for press, and 

 discussion of the Ben Nevis observations. 



The photographing of clouds and other meteorological pheno- 

 mena has been actively prosecuted at the Observatory, and re- 

 sults of considerable interest and importance have been already 



obtained. Selections from the photographs were exhibited by 

 the Scottish Meteorological Society and by the Royal Meteoro- 

 logical Society during the winter session. Of these photographs 

 four are submitted with this Repoit — viz, (i) a photograph or 

 St. Elmo's fire ; (2) a cloud photographed at midnight of June 

 last year ; (3) a remarkably fine photograph of a cloud, partly 

 made up of flattened mass-es, which is occasionally formed in 

 n^^ountainous districts ; and (4) photographs of crystals on the 

 Observatory and instruments outside. 



Mr. Rankin has extended and amplified his investigation of 

 the cases of St. Elmo's fire recorded at the Observatory ; and 

 the results, which are interesting and suggestive, have been 

 published in the Journ. Scot. Meteor. Soc. 



Mr. Omond has entered on an investigation of the relations of 

 the wind direction on the top of Ben Nevis to the sea-level 

 isobaric of the district at the time, and to the storms advancing, 

 on the Atlantic towards Norih- Western Europe, as shown on 

 the daily weather charis of the northern hemisphere published 

 by the Meteorological Institutes of Germany and Denmark. 



This is properly only the commencement of a large discussion> 

 of the Ben Nevis observations in some of their more practical 

 aspects, which will be undertaken and pushed forward next year 

 on the plan referred to in last year's Report, as rapidly as the 

 means at the disposal of the Directors of the Observatory will 

 admit. 



This season (1889) the snow disappeared from the summit of 

 the mountain in the middle of May, being about a month earlier 

 than in any previous year, and seven weeks earlier than in 1885; 

 and during the month of June the spiing near the Observatory, 

 and about 60 feet lower down, frequently ran dry, so that for 

 some time water had to be carried on horseback a distance of 

 two and a half miles. 



The Directors have had under consideration a proposed sys- 

 tematic observation of the numbers of dust particles in the atmo- 

 sphere with the instrument recently invented by Mr. John- 

 Aitken, and they are of opinion that the Ben Nevis Observatory 

 is the best place for making the observations in the most satis- 

 factory manner. Mr. Aitken will himself superintend the con- 

 struction of the two instruments which are required, and will see 

 to the placing of the stationary one in the Observatory, and its 

 connections with the atmosphere outside, in suitable positions, 

 and give directions as to the portable one designed as a check in- 

 strument, and for observations made at various distances from 

 the Observatory. Application has been made for a grant from 

 the Government Research Fund to aid in carrying on this novel- 

 and important research. 



Mr. Aitken recently visited the Observatory, and ten observa- 

 tions of the numbers of dust particles on the top of the mountain- 

 were made by Mr. Omond and himself, with the results that the 

 numbers per cubic centimetre rose from 350 at noon to 500 at 

 3 p.m. This result of the first observation is interesting and 

 suggestive. The purest air previously obtained by Mr. Aitken- 

 anywhere was on the Ayrshire coast, and on that occasion the 

 numbers were 1260 per cubic centimetre. It may be also ob- 

 served that the numbers on Ben Nevis rose from noon to 3 p.m.^ 

 the observations being made at the time of the day when aerial 

 currents from lower levels ascend along the heated sides of the 

 mountain to the Observaiory. 



In January last the Directors accepted an offer from the 

 Meteorological Council that, on being satisfied that provision 

 had been made for the maintenance of a Low Level Observatory 

 at Fort William, they would supply and erect in the Observatory 

 the self-registering instruments and otherwise complete the ordi- 

 nary outfit of meteorological instiumenls, and make an annual 

 grant of £2^^ towards its maintenance, and also continue the 

 grant of ;i^ioo yearly under the present arrangement. 



Since last Report, the Directors have received a legacy of 

 ;^5oo bequeathed to the f observatory, by the late Mr. R. M. 

 Smith, who was one of the Directors ; and a grant of ;,^ 1000 from 

 the Association of the Edinburgh International Exhibition of 

 1886 from the Surplus Fund of the Exhibition. A suitable site 

 for the Low Level Observatory was procured in Fort William, 

 and plans of the buildings were prepared by their architects,. 

 Messrs. Sydney Mitchell and Wilson, which were submitted to 

 the Directors and the Meteorological Council, and approved of. 

 The building is now well advanced, and it is expected that 

 the Observatory will be opened towards the end of the 

 autumn. 



The Directors of the Observatory and your Committee in their 

 successive Reports from 1884 insisted on the absolute necessity 



