754 



NA TURE 



[June io, 1922 



bare facts are not enough : it is necessary to be able 

 to seize the essential characteristics of a country and, 

 discarding unimportant details, to bring those essential 

 characters together in a connected whole, in order to 

 give a clear and definite impression that will readily 

 implant itself upon the mind. This work. Sir F. 

 Younghusband said, does not involve the problem of 

 transport : it can be done far better on foot, and the 

 homeland explorer does not even require the qualifica- 

 tion of youth. " We [must] gather to us men with 

 eyes to see, and hearts to feel, and heads to think, 

 who will be fired with enthusiasm to explore round 

 about their own homes and then come here and 

 describe to us what they have seen." 



The March number of the Tropical Agriculturist 

 contains an account of the work at the Royal Botanic 

 Gardens, Peradeniya, Ceylon, the centenary of the 

 establishment of which occurs this year. In 1810 Sir 

 Joseph Banks drew up a plan for a botanic garden 

 which was established two years later at Colombo. 

 In 1822 the work was transferred to Peradeniya, near 

 Kandy, the site of the late Kandian king's garden, 

 under the superintendence of Alexander Moon. The 

 first plan of the garden, which was 147 acres in extent, 

 is now in the Library of the Royal Horticultural 

 Society in London. Work of development, begun in 

 earnest in 1844, with the appointment of George 

 Gardner, received a temporary check on Gardner's 

 death in 1849, but in the next thirty years, under the 

 superintendence of G. H. K. Thwaites, the gardens 

 attained considerable fame. Thwaites was succeeded 

 in 1880 by Henry Trimen (1880 -1896) who, con- 

 tinuing Thwaites' investigation of the flora of the 

 island, brought out the well-known " Handbook of 

 the Flora of Ceylon." J. C. WiUis succeeded Trimen, 

 but retired in 191 1, when the gardens were placed 

 under the newly constituted Department of Agri- 

 culture. Peradeniya has played an important part 

 in the agricultural development of the colony in 

 connection with the introduction and acclimatisation 

 of plants of ornamental and economic value. The 

 chief interest was coffee until the industry was ruined 

 by the coffee-leaf disease, when it was replaced by 

 cinchona and subsequently tea. The rubber industry 

 of the East owes much to the work in Ceylon, where 

 seedlings were transferred from Kew in 1876 ; in 

 1906 the first of the World's Rubber Exhibitions was 

 held in the Peradeniya Gardens. In 1887 a small 

 botanical laboratory was fitted up in the gardens, and 

 many British and Continental botanists have taken 

 advantage of the facilities thus afforded for the study 

 of botany in the tropics. In 1900 this was replaced 

 by a larger well-equipped building. 4^ 



The third annual report of the Governors of the 

 Imperial Mineral Resources Bureau, which has 

 recently been issued, contains much interesting 

 information. It is gratifying to see that at last a 

 serious attempt is being made to adopt a unified 

 system of mineral statistics applicable to the whole 

 of the British Empire. This reform is long overdue, 

 and it is to be sincerely hoped that the present 

 effort will meet with success. The greater part of 



NO. 2745, VOL. 109] 



the report is devoted to a general review of the 

 mineral industry of the British Empire and foreign 

 countries for the year 1921, and the importance to 

 the industry of such a comprehensive review at so 

 relatively early a date can scarcely be overestimated. 

 Even if the figures given are only approximately 

 correct, they will serve as a trustworthy guide to 

 the general trend of the industry. Unfortunately the 

 picture is a very gloomy one, being a practically 

 uniform chronicle of world-wide depression ; almost 

 the only exception is to be found in the coal production 

 of Germany, which shows an appreciable improvement 

 on that for 1920, and in the words of the report, 

 " Considering the loss of the coal production of the 

 Saar, the approach of Germany's fuel production in 

 1 92 1 to the pre-war figures is significant." 



A LECTURE on the mechanical construction of the 

 microscope from a historical point of view, given by 

 Prof. Alan Pollard before the Optical Society on 

 April 27, dealt with the evolution of the instrument 

 from the earliest times until about the middle of the 

 nineteenth century. Prof. Pollard divided his subject 

 into two main periods — the non-achromatic, in which 

 the early history of the single lens or simple micro- 

 scope was dealt with, and the achromatic. The 

 mechanical details of outstanding historical compound 

 instruments of these two periods which marked the 

 progress of mechanical construction to the modern 

 compound microscope, were described. Many famous 

 instruments of the first period, such as John Marshall's 

 " New Invented Double Microscope " of 1693, 

 Culpeper's " Double Reflecting Microscope " of 1735, 

 Cuff's " Double Constructed Microscope " of 1744, 

 B. Martin's simple and compound instruments of 

 1765, Bleuler's " Universal " of 1788, Jones' " Most 

 Improved " of 1798, by DoUond, Gould's " Pocket 

 Microscope" of 1828, by Cary, as well as Lister's 

 famous compound microscope, by James Smith in 

 1826, which marked the opening of the second period 

 in this country, were set up with histological specimens 

 so that their mechanical and optical performances 

 could be compared. In addition, early catoptric 

 instruments were shown, including Amici's reflecting 

 microscope, made for Dr. WoUaston in 1830. The 

 development in particular of the modern English 

 limb from the Lister and Jackson designs, and the 

 so-called continental limb from the early forms of 

 Oberheuser and Nachet, was traced and described. 



The gold medal of the Linnean Society of London, 

 which is given in alternative years to a botanist and 

 a zoologist, was this year awarded to Prof. E. B. 

 Poulton at the anniversary meeting on May 24. In 

 making the presentation, the president. Dr. A. Smith 

 Woodward, referred to Prof. Poulton's long labours 

 in entomology, and his keepership of the Hope 

 Collection at Oxford, transformed by him into a great 

 museum, illustrative of variation, mimicry, and evolu- 

 tion. Prof. Poulton, in replying, mentioned the fact 

 that half a century had elapsed since his matriculation 

 at Oxford. At the same meeting of the Society the 

 following officers were elected : President : Dr. A. 

 Smith Woodward ; Treasurer : Mv. Horace W. 



