January 12, 1905] 



NA TURE 



261 



ledge of the standards of measurement necessary for the 

 investigation of physical phenomena. The need for a co- 

 ordination of the elementary instruction in arithmetic and 

 geometry was emphasised by subsequent speakers. 



The third annual meeting of the North of England 

 Education Conference was held in Liverpool on January 6 

 and 7. More than 2000 members of education committees, 

 teachers, and others attended. The question of leaving 

 certificates was discussed at the first meeting, and during 

 the course of the discussion Sir Oliver Lodge said the use 

 and not the abuse of examinations is admitted by all as an 

 adjunct to teaching, but the point is to determine the re- 

 lation between teachers and e.\aminers, also between 

 teachers and inspectors. People are no longer going to be 

 satisfied with purely external examinations imposed from 

 above upon the schools. It is not a dignified position for 

 the schools, and they have rebelled. Prof. Sherrington, 

 F.R.S., read a paper later on child study, in which he urged 

 that this study could not devote itself more profitably at 

 the present time than to what may be termed the natural 

 history of the child. In healthy school life lay the first line 

 of defence against race deterioration. It would help 

 society if teachers and physiologists could combine to 

 examine into the mischief to growth resulting from hours 

 of breathing vitiated air, from want of warm clothing that 

 economised food, from semi-starvation, from improper food, 

 from chronic fatigue, and from insufficient rest and sleep 

 in bed. Among other subjects dealt with were the teach- 

 ing of geography, the teaching of domestic science, and 

 the place of handwork in the school curriculum. 



A DEPUTATION from the executive committee of the 

 Association of Education Committees (England and Wales) 

 recently waited upon the Board of Education to urge the 

 adoption of a more liberal scale of grants for secondary 

 schools, to ask for a larger share from the Government of 

 the cost of training pupil teachers, and to urge the necessity 

 for the compulsory attendance up to the age of fourteen at 

 evening continuation schools of all children who do not 

 continue as whole-day scholars up to that age. Sir William 

 Anson, in reply to the deputation, agreed that more money 

 should be allowed to secondary schools, but though such a 

 demand would have his support. Sir William Anson said 

 he was by no means sure of obtaining the necessary funds. 

 He expressed the opinion that the question of cost made it 

 almost impossible to enforce a system of compulsory attend- 

 ance at evening continuation schools up to fourteen years of 

 age for children leaving the day school before that time. 

 Until we have better security that the education given in 

 the elementary school lasted, and a better secondary educa- 

 tion system with larger grants for secondary schools. Sir 

 William added, he would not be a party to asking for another 

 penny for elementary education, as such. It is satisfactory 

 to find it recognised officially that this country must spend 

 more money on secondary, and technical education if we 

 are to have an educational system which will assist national 

 progress. 



The annual meeting of the Geographical Association was 

 held on January 6. Mr. Douglas Freshfield presided, and 

 an interesting discussion took place on the teaching of 

 practical geography in schools. Prof. Dryer, of the State 

 Normal College, Terre Haute, Indiana, opened the debate, 

 and said that practical geography meant in America 

 laboratory work. This work is not necessarily done in a 

 special room, and, indeed, the best part of it is done out 

 of doors. The study of maps plays a large part in this 

 laboratory work. Contoured topographical maps are also 

 much used, together with raised models illustrating different 

 forms of the earth's surface. Pictures, photographs, and 

 lantern slides also have a conspicuous place in the school's 

 ■equipment. The instrumental study of the earth's atmo- 

 sphere is taken next by the students, who keep records of 

 their own observations for a period of three months. The 

 official weather charts can be obtained daily at every school, 

 and, owing to the area covered by them, it is possible to 

 follow cyclonic and anti-cyclonic disturbances for several 

 days together, and sometimes to predict in the school itself 

 the arrival at a particular time of an atmospheric disturb- 

 ance. Field excursions are regarded as the most important 



NO. 1837, VOL. 71] 



part of geographical study. Mr. B. B. Dickinson described 

 an experiment in the teaching of practical geography carried 

 out by him at Rugby School. The report of the association 

 shows that 123 new members have been added to the roll, 

 making the total membership 448. The members now in- 

 clude teachers of every grade, school inspectors, directors 

 of education, technical education committees, and others 

 interested in geographical education, both at home and 

 abroad. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, December I, 1904. — "The Ascent of 

 Water in Trees." By Dr. Alfred J. Ewarti Lecturer on 

 Botany in the University of Birmingham. 



Since the time when Strasburger's researches seemed to 

 show that the ascent of water in trees was a purely physical 

 phenomenon, attempts have been made by Dixon and Joly, 

 as well as by Askenasy, to prove that the ascent of water 

 is due to a tensile stress set up by transpiration in the 

 leaves, and transmitted downwards by continuous water- 

 columns which are practically suspended from them. A 

 knowledge of the resistance to the transpiration current in 

 the stems of trees, and of the influence of various factors 

 upon it, forms, however, an essential preliminary to any 

 such explanation. 



The author finds that when the vessels are completely 

 filled with water and are open at both ends, the flow through 

 them takes place in accordance with Poisseuille's formula, 

 the rate of flow being directly proportional to the pressure 

 and inversely proportional to the viscosity of the liquid and 

 the square of the radius of the vessel. Hence in climbing 

 plants where a rapid rate of flow is required the vessels 

 are large, approaching i mm. in diameter, and in such 

 cases the total viscosity resistance during average trans- 

 piration is equal to a head of water considerably less than 

 the height of the stem. Under normal conditions, however, 

 air bubbles always appear in the conducting vessels of 

 angiospcrmous trees, and each bubble exerts a resistance 

 to flow which is directly proportional to the surface tension 

 of water against air and inversely proportional to the radius 

 of the tube. In a tall tree the theoretical resistance due 

 to this cause alone might amount to as much as 300 atmo- 

 spheres, whereas calculations from direct experiments gave 

 total resistances for the tallest trees of 100 atmospheres 

 during active transpiration. 



No leaf could produce or maintain an osmotic suction of 

 this intensity, nor could the water columns in the vessels 

 transmit it without rupture. In addition, actual observ- 

 ation showed that although differences do occur in the 

 osmotic concentration of the cell-sap in the leaves at different 

 levels, these are not sufficient to overcome the resistance 

 to average flow in the intervening portions of the trunk. 

 It appears, therefore, that a staircase pumping action must 

 be exercised in the wood of a tall tree, which enables the 

 leaves to obtain the water they require without their being 

 forced to exercise tensions of more than ^ to ^ of an 

 atmosphere. No satisfactory physical explanation of such 

 action has yet been given, but the author points out that 

 by appropriate surface-tension action along the length of 

 a Jamin's chain the water could be led upwards from water- 

 column to water-column, and maintained in a labile con- 

 dition ready to flow in any direction where moderate suction 

 was exercised. Various indirect estimations have been made 

 which lend support to this view, but direct observations 

 have not hitherto yielded satisfactory proof, so that further 

 investigations are still needed in this direction, and these 

 are, in fact, in progress. 



December 15, 1904. — " An Analysis of the Results from 

 the Falmouth Magnetographs on ' Quiet ' Days' during the 

 Twelve Years i8gi to 1902." By Dr. Charles Chree, 

 F.R.S. 



The paper contains an analysis and discussion of the 

 results obtained from the declination and horizontal force 

 magnetographs at Falmouth on quiet days from 1891, when 

 the records commenced, until 1902. 



The total secular changes of declination from 1891 to 

 iqoo at Kew and Falmouth were identical,, and the changes 



