32 



NATURE 



[November 9, 1899 



even then beginning to get scarce. These are now at the Royal 

 Institution. 



In all these prisms the end faces were the natural crystal 

 faces, only smoothed and polished ; and the plane of section 

 made an angle of 87° 30' with them, or 21° 30' with the length- 

 axis of the prism. 



In none of them was Canada balsam used as the cement (I 

 have not used it for this purpose for thirty years past), but a 

 special material. C. D. Ahrens. 



Swiss Cottage, King's Road, Upper Teddington, 

 October 13. 



AN ENGLISH STATION FOR BOTANICAL 

 RESEARCH IN THE TROPICS {CEYLON). 



THE Royal Botanic Gardens of Ceylon, under the 

 direction of Thwaites and Trimen, to go no further 

 back, have long been known as one of the most important 

 centres of scientific work in systematic and economic 

 botany. Thanks to the British Association for the 

 Advancement of Science, a small room next to the 

 director's office was fitted up as a laboratory, in which 

 have worked many botanists, chiefly English. Among 

 those who have worked in Ceylon during the last decade 

 may be mentioned Profs. Bower, Farmer, Goebel and 

 Potter, and Messrs. Freeman, Keeble, Pearson, Parkin, 

 and others. During the last two years the laboratory 

 has been very much overcrowded, being used by the 

 staff of the gardens as well as by visiting botanists. 

 With the commencement this year of a new research 

 laboratory, now being erected by the Department of 

 Public Works, and to be completed probably before the 

 end of the year, this difficulty will be overcome, and 

 there will be ample room for several workers from abroad 

 in addition to the members of the staff. This being so, it 

 may not be amiss to give at this time an account of the 

 facilities now available in Ceylon for research in the 

 tropics. While the laboratory is primarily intended for 

 botanical research, there is no intention of excluding 

 workers in other lines so long as there is room for them, 

 though of course money cannot be spent in providing 

 special apparatus for their work. 



The Royal Botanic Gardens form a department of the 

 public service in Ceylon, under a director. The head- 

 quarters of the department are at Peradeniya, near 

 Kandy, where the principal garden was established in 

 1 82 1 by Moon. There are now smaller branch gardens 

 in four other places in different climatic regions of the 

 island. A brief account of these may be of interest. 



The original Peradeniya garden lies within the muni- 

 cipality of Kandy, about four miles from the centre of 

 the town. It may be reached by driving in a carriage 

 or rickshaw, or by trains which run at intervals to a 

 station near the garden. The roads here, as almost 

 everywhere in the island, are excellent for cycling. The 

 garden has an area of about 150 acres, and lies in a 

 very beautiful situation, in a loop of the Mahaweli 

 river, and in very mountainous country. Its elevation 

 above sea is about 1550 feet, so that it has a much more 

 pleasant climate than the low country. During the day 

 the difference is but little, but the nights are very much 

 colder than in Colombo, so that refreshing sleep can 

 always be had ; indeed, during most of the year a 

 blanket is necessary. The mean annual temperature is 

 76° F., that of the hottest months (March and April) 

 being 79°, that of the coldest (January and June) 74-75^ 

 The highest shade temperatures ever reached are not 

 excessive, rarely exceeding 90", and in the present 

 laboratory the highest in the last two years has been 82°, 

 the lowest 65°. Work can thus be carried on with as 

 little discomfort as in any European laboratory. The 

 annual rainfall is about 90 inches, but owing to the great 

 violeiice of tropical rain the number of rainy hours or 

 days is very much less than in England. The number 



NO. 1567, VOL. 61] 



of days with rain averages 170 per annum, and it rarely 

 rains more than four hours on any one day. Rain in the 

 morning is also rare. The weather of the year depends 

 on the monsoons. In the end of May the south-west 

 monsoon begins to blow, and there is much wind and 

 rain, the weather gradually becoming finer through the 

 months of June and July. August and September and 

 the first half of October are delightful months. In 

 October the north-east monsoon begins, and until 

 Christmas it is very wet. In January begins the "dry 

 season," and during the next two or three months there 

 is less rain than at any other time of year, and the 

 weather becomes gradually very hot, though until April 

 the nights are cold. March and April are the only really 

 unpleasantly warm months in the year. The best time 

 on the whole to visit Peradeniya is from October to 

 March, but from July onwards is very nice, the objection 

 to travelling at this time from Europe being the heat in 

 the Red Sea, which, however, is much less formidable 

 than is usually supposed in these days of swift boats and 

 ice chambers. 



The garden contains a splendid collection of tropical 

 plants, and, being arranged like an English park, with 

 wide spaces of lawn, the specimens are easily seen and 

 photographed. In the centre lie the buildings of the 

 museum, library, herbarium and laboratory, close to- 

 gether. The museum is chiefly devoted to the economic 

 products of Ceylon, and contains a very good and in- 

 teresting collection. The herbarium consists primarily 

 of Ceylon plants ; but there is also a general tropical 

 herbarium, and a herbarium of the plants contained in 

 the gardens. In the same building is the library, which 

 contains about two thousand books and papers. There 

 is an excellent collection of books relating to economic 

 and systematic botany, and recently a large number ot 

 works on the other branches of botany have been added ; 

 a considerable number of journals is also received regu- 

 larly, including such periodicals as the Annals of Botanyy 

 Botanical Gazette, Botanische Zeitung, Flora, &.c. 



The laboratory lies a few yards to the north of the 

 herbarium (a plan is given on p. 33). It consists of a one- 

 story bungalow of brick on a stone foundation, and with 

 cement floor and tiled roof The length of the building 

 runs approximately east and west, and on the north and 

 south sides there are no verandahs. At the east end 

 is a verandah 8 feet wide, the ends of which are built up 

 so as to form — one a lavatory, the other a dark room for 

 photographic work, fitted with sink, &c. At the west end 

 is also a verandah of the same size, not built up in any 

 way. 



The building has six entrances, provided with French 

 windows, two at each end and two on the south side. 

 The other windows stand above the ground, and open 

 outwards. There are doors leading from each room into 

 all the adjacent rooms, so that free ventilation can be 

 obtained, and at the same time any room can be com- 

 pletely shut up if required to prevent draughts without 

 interference with the accessibility of the others. 



The principal room, the general microscopic and 

 morphological laboratory, lies to the north-west, and is 

 36 feet long and 18 feet wide. It has four working 

 windows facing north, each with table, shelves, sink, &c., 

 and two other windows facing into the west verandah, 

 which can also be used as microscoping windows if 

 required. The central part of the room will contain 

 larger tables for microtome and other apparatus, and 

 writing table. 



To the east of this room is the smaller room devoted 

 to physiological and pharmacological investigations. 

 Leading out of this room is a French window, which 

 gives access to the little eastern verandah, which may be 

 used for cultivation expermients, &c. This room has 

 two good working windows facing north, besides the 

 French window. It is provided with three sinks and a 



