July 8, 1920] 



NATURE 



599 



The administration of the engineering foundation 

 is conducted by sixteen members elected by the United 

 Engineering Society, thirteen of whom must be 

 members of the founder societies. Although finally 

 organised only in the early part of 1915, the founda- 

 tion has become thoroughly established, and is 

 carrying on a most admirable work. 



A. P. M. Fleming. 



African Softwoods for Pulp Production. 



By A. H, Unwi.n, 

 Late Senior Conservator of Forests, Nigeria. 

 A BOUT the year 1907, at the instigation of the late 

 -^*' Sir Alfred Jones, an inquiry was addressed to the 

 West African Colonies with regard to the softwoods 

 suitable for paper or pulp production. As a result a 

 list was compiled for the Benin country, which 

 included some twenty species of whitewood. Since 

 that date little or nothing has been done towards the 

 solution of this problem. Nevertheless, much greater 

 knowledge has been obtained of the softwoods of the 

 West Atrican Colonies — the Gambia, Sierra Leone, 

 Gold Coast, Nigeria — and of West Africa generally. 



Although baobab {Andansonia digitata) has been 

 suggested as suitable, it is usually found rather remote 

 from navigable waterways, and in such scattered 

 quantities that it is doubtful if its exploitation will 

 pay. On the other hand, the wood of the cotton-tree, 

 Eriodendron anfractuosum and E. orientale, has 

 been adversely reported upon, but it does not appear 

 that very exhaustive experiments were made with 

 either of these species. The ease of its production, 

 the rapidity of its growth, and the softness of its 

 wood would seem to commend the cotton-tree for pulp 

 production. The wood of Bombax buonopozense may 

 also be of use. 



Perhaps a more suitable wood will be obtained from 

 the African maple, Triplochiton Johnsonii and T. 

 nigericum. The wood of both these species is of 

 about the same hardness as that of spruce. It is of 

 a similar colour, and the fibres are long. The tree is 

 verv prevalent, its reproduction easy in the proper 

 localities, and its growth rapid. On average soil 

 the trees reach pulp- wood size within ten years, and 

 there are many specimens even in seven years. 



In certain localities the occurrence of Sterculia 

 Barterii is such as to redden the hill-sides with 

 its flowers in March The growth of the tree is very 

 rapid, and the wood is fibrous and porous. The tree 

 will attain pulp-wood size in five years. In suitable 

 localities the natural reproduction from mature trees 

 is rapidly filling the whole forest. 



Other Sterculiae, such as tomentosa. rhinopetala, 

 and tragacaniha, might be used. Of these the last- 

 named appears to be the most suitable. It is also 

 verv prevalent, and grows rapidly. The wood of 

 Sterculia rhinopetala may prove to be a little hard, 

 hut with modern means of pulping it may be possible 

 to use all these species at the same time. 



The quantitv of bamboo on the West Coast of 

 Africa is negligible, though the area of its distribution. 

 is i/radually widening. 



The Albizzias usually produce in their vounger stages 

 a whitish-vellow softwood. Most species grow very 

 fast, and would vield pulp-wood within ten years. 

 The wood shows long fibres! Owing to the prevalence 

 of the tree in the forests, there would be no difTicutty 

 as to the quantity. The wood of Terminalia superhd' 

 should prove of value, though its brownish tinge mav 

 have to be removed in order to make the best-roloufed 

 pulo. It is prevalent and its growth is rapid. 



Another very common tree is Alstonia congensis, 



NO. 2645, VOL. 105] 



which Is often found in the swamps as well as in the- 

 rnoist forests. Its growth is very rapid, and it would 

 yield pulp-wood in seven years. Owing to its pre- 

 valence, this softwood with its longish fibre should 

 prove of value. 



The wood of Ricinodendro'n Heudelotti appears to 

 be suitable, though the colour is dull grey-brown. 

 The tree is very prevalent, and its natural regenera- 

 tion prolific. It reaches pulp-wood size within a 

 period of seven to ten years. Pycanthus kombo 

 is another tree which appears to yield a suitable 

 species of timber. It is very prevalent, the wood 

 is soft and fibrous, and natural reproduction is great. 

 Even the much-despised Musanga Smithii might on 

 occasion be used to supplement inadequate supplies of 

 other pulp-wood timbers. Near the rivers in some 

 districts there is a common tree named Otu, which 

 is planted by the natives. It yields a soft whitewood 

 which has a longish fibre. 



With the great shortage of paper-pulp it appears 

 that the utilisation of these West African species of 

 trees should be undertaken as soon as possible. 

 Naturally, it will mean a good deal of experimental 

 work, . but with the experience already gained in 

 Canada and.Norv^ay and Sweden it should be possible 

 to produce pulp below existing cost. Although African 

 labour is expensive as compared with Indian or 

 Burman, it has proved itself thoroughly adaptable to 

 training in the use of complicated machinery such as 

 that employed in shipbuilding and in oil- and saw-mills. 



With a population of about sixteen millions of people 

 in Nigeria alone, it has been found possible gradually 

 to obtain sufficient men for a new industrv. 



Effect of Topography on Precipitation in 

 Japan. 



CONSIDERABLE attention has been directed 

 recently to the subject of the orographical dis- 

 tribution of rainfall, and results obtained in different 

 places are liable to lead to general deductions, not 

 only independent, if not quite contradictory, but also, 

 on the face of them, improbable. We may instance an 

 alleged connection between Indian monsoon intensity 

 and the extent of local water surfaces, and also 

 M. Mathias' cartographical demonstration that the 

 increase of precipitation with altitude is directly 

 dependent on the latitude, at any rate in France. Mr. 

 Carle Salter's lecture to the Institution of Water 

 Engineers on the relation of rainfall to configuration 

 gave little ground for suspecting either of these possi- 

 bilities. 



At first sight. Prof. Terada's contribution in the 

 Journal of the College of Science, Tokyo Imperial 

 University (vol. xli., art. 5), appears to be only a 

 supplement to previous work of Profs. Nakamura and 

 Fujiwhara, but one or two comparatively fresh notes 

 are struck. Prof. Omori had previously found a cor- 

 relation between earthquake frequency in some dis- 

 tricts and precipitation in others. This is now 

 described by Prof. Terada as a case more of 

 parallelism than of cause and effect, for he prefers 

 to attribute both phenomena to barometric changes 

 rather than to associate the instability of the soil with 

 percolation. His main purpose, however, is to study 

 the effect of the discontinuity of wind velocity on 

 land and sea, and for this purpose he divides Japan 

 into six districts, three facing the ocean and three 

 the Japan Sea, and in each district chooses two or 

 three stations near the coast. ' ^ . 



The three "ocean" divisions show a rna^-ked increase 

 in rainfall with decrea^pg platitude, but. on the con- 



