214 



NA TUKE 



[December 30, 1897 



Such records have been made for more than thirty years in 

 France and Germany, and surely we must have here, if any- 

 where, a sufficient proof of a forest's influence. 



Admitting that we have perfect instruments and careful 

 observers, there still remains a most serious doubt as to the 

 immediate environment of each gauge and as to the possibility 

 of a direct comparison. It is probable that no two gauges 

 2000 feet apart can be placed so as to catch the same amount of 

 rain, though to all appearances the exposure is faultless in each 

 case. 



Extreme caution is therefore needed in arriving at conclusions 

 from comparisons between gauges in forests and in the open. 

 One of the best of all researches in this line ha^ been conducted 

 at Nancy, in France. Within a distance of five or six miles 

 there have been four stations established. At Nancy in the open, 

 and at Belle-Fontaine in the forest ; and, 500 feet higher 

 vertically, Amance (open) and Cinq-Tranchees (forest). At 

 Nancy and Belle-Fontaine the observations extend over twenty- 

 five years. A comparison of the records in groups of eight, eight, 

 and nine years was made, with the result tliat while the first eight 

 years showed a very slight excess in the forest rainfall over that 

 in the open field, in the last nine years (including 1894, last 

 published) the open station showed a little more rain than the 

 forest station. These observations were made with particular 

 care, for the purpose of exactly determining the influence, and 

 may be relied on if the environments of the gauges were com- 

 parable. At Amance (open) and Cinq-Tranchees (forest) the 

 observations have not been quite so regular, though there are 

 twenty-five full years of records at these two stations, but not 

 the same years as at the other stations. The comparison in this 

 case makes the rainfall more than 20 per cent, greater in the 

 forest than in the open. It should be borne in mind, however, 

 that these two stations are on an eminence, and are not strictly 

 comparable, and this result cannot vitiate that at the two other 

 stations, which shows no effect. 



In Germany we have a rather remarkable record of a slightly 

 different character, Linfzel is a station on the Luneburg Heath, 

 which began to be planted with trees in 1887, at the rate of 

 1000 to 1500 acres a year, and in a few years over 8000 acres 

 were covered. In the midst of this forest is the meteorologic 

 station in an open field of some seventy-five acres. Before 

 planting the forest, 97 per cent, of the surface was field, meadow, 

 or heath, and afterwards 80 per cent, was forest and 20 per cent, 

 was roads, open field, and heath. Around this station, pretty 

 evenly distributed, and within fifty miles, there are thirteen 

 rainfall stations which have been carefully established, and pre- 

 sumably are comparable with the Lintzel station in the midst of 

 the growing forest. There are no means of knowing whether 

 any of these stations have been changed or not, but for our pur- 

 pose we may consider the material homogeneous, and treat it 

 accordingly. Records from 1882 to 1896 (fifteen years) are 

 available. Charts were prepared for each year showing the 

 ratio between the Lintzel record and that at each station of the 

 thirteen. The results do not show that the afforestation has 

 had any appreciable effect upon the precipitation; in 1884 the 

 ratio was loi, while in 1893, nine years later, it was 96. It is 

 probable, however, that no definite and unassailable result can 

 ever be obtained either by the method adopted in France or this 

 later one in Germany. The rainfall is so variable within a 

 distance of even a mile or two ; and it is so difficult, if not im- 

 possible, to obtain similar environments at all the stations, that 

 no decisive result can be obtained. It will be readily seen that 

 the multiplication of stations will do no good, and, above all, 

 that the observation of rainfall under trees in a forest is ab- 

 solutely useless for any such discussion or study as this. 



Need of Further Evidence. 



It seems probable that if two or three lines of stations could 

 be established a mile or two apart on four sides of an enormous 

 forest, each line to have a dozen stations or so, about 3000 feet 

 apart, four of the stations to be outside of the forest, and the 

 others each in a large cleared space of at least two acres extent 

 in the forest, something decisive might be obtained. It should 

 be noted, however, that from the evidence already accumulated 

 there would be very little to be gained by a further study of the 

 question. It is certain that the effect, if there be one, is almost 

 inappreciable. The favouring conditions over the forest are 

 balanced by those not favouring, and the integrated effect is 

 practically the same in the two cases. 



Prof. H. F. Blanford determined from a most careful 



NO. T47O, VOL. 57] 



series of records, from which all known errors had been 

 eliminated, that the forest had a tendency to give 2 per cent, 

 more rain than contiguous open fields. That is, if an open place 

 had 50 inches of rain in a year, a near-by forest would have only 

 51 inches, which is practically inappreciable. 



It would be an interesting study to select all those cases in 

 experiments in forest and near-by fields in which the wind was 

 blowing either from the forest to the field, or vice versa. It is 

 evident that if there is any effect on rainfall by the forest, it 

 would be vitiated, if not exactly reversed by such winds. 



There is a class of visual observations which seem to show an 

 effect upon rainfall by the forest. Probably many have seen 

 heavy clouds passing over a plain, but which only precipitated 

 as they passed over a forest. Also in a hilly region it is a frequent 

 phenomenon that fog and low-lying cloud hover near a forest, 

 and not over an open plain. One also notes very often, in 

 passing into a forest on a damp day, that the trees drip moisture, 

 possibly condensed from moisture evaporated from the damp 

 earth underneath. Observations of this nature, however, cannot 

 ordinarily be checked by instrumental means, but show in a 

 general way that the forest tends to conserve vapour and 

 moisture which in the case of the open field would be diffused 

 into the atmosphere. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Dr. G. H. Rendall, the Principal of University College, 

 Liverpool, has been appointed Head- Master of Charterhouse 

 School. 



Sir John Gorst, in the course of an address at Bristol on 

 Thursday last, is reported by the Times to have said that the pro- 

 motion of technical education was confronted by two obstacles — 

 the backward condition of elementary education and the want of 

 organisation in the provision of secondary education. A good 

 sound system of elementary education must be the groundwork for 

 higher education, and he urged reform of the system which at 

 present relieved children from compulsory attendance when in- 

 adequately equipped. The improvement of the organisation of 

 secondary schools was really a matter for the people them- 

 selves. There was nothing to prevent technical instruction com- 

 mittees from becoming thoroughly representative and effective 

 organisations. 



The most satisfactory point to us in the Report just issued by 

 the Oxford University Extension Delegacy refers to the Ex- 

 tension College at Reading. The college is doing excellent 

 work, more particularly in agriculture, and has amply justified 

 its existence. New buildings are, however, imperatively needed, 

 and in response to an appeal for 12,000/., 9,000/. has already 

 been promised, and the new wing has been begun. The build- 

 ing scheme, planned four years ago, will be completed by next 

 summer, and H.R.H. the Prince of Wales has promised to 

 perform the opening ceremony. The educational work of the 

 college has been attended with great success during the past 

 year. With regard to the courses of lectures delivered under the 

 auspices of the Delegacy during the year 1896-97, we notice 

 that out of a total of 146 courses, only nineteen were on scientific 

 subjects. 



In the course of a presidential address recently delivered 

 before the Kansas Academy of Sciences, Prof. S. W. Williston 

 severely criticised the system of education which makes language 

 studies compulsory, and all, or nearly all, the sciences optional. 

 Many educationists will find themselves in agreement with the 

 following opinions expressed by Prof. Williston: — "I claim 

 broadly and emphatically that the natural sciences, any or all of 

 them, are as valuable and as necessary as pure cultural studies as 

 are the languages ; that intelligent and successful study of them 

 will do as much, if not more, in making the student a broad 

 man, a successful man, as will the study of Latin or Greek. 

 And they will do more in making him an honest man. Nowhere 

 in all the broad field of knowledge will he learn better to think 

 exactly than in the natural sciences. Nowhere will he be more 

 impressed with the importance of truth for truth's sake. . . . Were 

 I, then, to say what the universities and colleges ought to do, it 

 would be this : make all the ancient language requirements for 

 admission optional, and demand as much preparation in the 

 physical and biological sciences as in the foreign languages. 

 The preparation in English should be made far more rigorous 



