2'JO SOME MUNICIPAL ENGINEEEING TKOHLEMS IN THE TEOPICS 



of water and fairly good soil. This also applies to l>aJlifr<//ii aisauo, and Baiiliiiiia ijurjnu'ii 



with its handsome flowers. 



'^f^'=' °' Owing to the variation in the soil met with iu Khartoum one cannot always be certain 



variations in . . mi i -i r • !■ t i 



soil on trees °' success in tree planting. The best sou, of course, is found along the river Embankment 

 where the Alhizzia Inljlivl; and Alhizzia procera make handsome trees in five or six 

 years. In other parts of the town there is a light soil consisting mostly of drift sand in 

 which, when once established, the Lebbek does well. The most troublesome soil in which 

 to get trees to flourish is in Victoria Avenue, where there is a stiff clay soil full of salts 

 and almost impervious to water. After many trials, Ficioi hpiiyale)ii<i,s (Banyan) has been 

 planted and is making rapid progress. 



The trees are planted 10 metres apart, and, if in a double row, alternately with 

 five metres between the rows. When planting, it is in most cases advisable to dig a hole 

 one metre deep and refill it w-ith good soil. The trees, if small, require shading for 

 some days until established, and in some parts of the town goats have given considerable 

 trouble, and it is necessary to protect the young shoots from being eaten. Wire netting 

 one metre wide, supported by two strands of telegraph wire, has proved quite a success, 

 although when the growths reach the top of the netting they are often broken by children 

 and animals. 



Staking the young trees is most important, and as one has to contend against strong 

 winds and white ants it is difficult to find a cheap and suitable support to prevent their 

 being broken. When quite small a stout bamboo stake is the best support and lasts 

 some time, but when the tree has a fair sized head, a 3 inch x 3 inch telegraph pole 

 13 feet long, painted with " solignum " or other preservative, is used. 

 Watering \\\ f^jjg trees Were at one time watered by native women who carried the water in jars 



of trees \ i ■ i i 



(burmas) on their heads, a very slow method : but now water-carts drawn by mules 

 and filled at the street stand pipes, have proved much more efficient. 



An earthen basin is formed round the tree to retain the water, and in tiled or 

 other footpaths it is necessary to leave a sufficient opening and desirable to provide a 

 grating on top of this basin. 



Fig. 83 is a photo of the Embankment roadway, which shows the excellent shade 

 provided by the "Banyan" trees on the left, and also the strong roots already referred to. 

 The trees on the right side of the road are " Lebbek." 



ITT. BriLDiNCiS 



The provision of suitable buildings, both for public and private purposes, is of primary 

 importance. How often one sees in the Tropics buildings of a type quite unsuited to 

 the local conditions, and sometimes even a purely European type may be found. Much 

 may be learnt from a study of the native type of dwelling, and although it may be necessary 

 to modify it considerably to suit the European mode of life, yet many of the underlying 

 l^rinciples should be maintained. 



Before proceeding to the consideration of the requirements in a dwelling to meet 

 the conditions at Khartoum, it would be well to review the history of building operations 

 there subsequent to the allotment of lands in the new town and the relative regulations 

 issued from time to time, as these have had some influence on existing types. 



In the paper' already referred to the early building operations are thus described. 



' " Planning of Khartoum and Otndurman " 



