March, 1912.] 



217 



Timbers, 



It will be seen from the above that, 

 roughly, three times the weight of tuber 

 was treated in 1910, as compared with 

 the figures for 1909, with an equivalent 

 increase in the marketable article, A 

 great deal of the latter finds its way to 

 the Southern markets, where it meets 

 with a ready sale. There was only 

 246,064 lb, made in 1909, which was a year 

 of partial failure. During 1910 the quan- 

 tity manufactured was 718,636 lb., but in 

 these days of facile transport a commo- 

 dity of a non-deteriorating nature does 

 not glut the market or materially affect 

 the standard retail price. Naturally the 

 produce of one calendar year is dealt 

 with commercially during the year fol- 

 lowing; but the statement above, though 

 only supplying figures to the end of 1909 

 (those relating to imports and exports 

 for 1910 not being available), shows that 

 there has always been a considerable 

 proportion of our arrowroot sent out of 

 the State. 



BUTTER NUT. 



The Butter-nut, or Sonari-nut, known 

 botanically as Caryocar nuciferum, is a 

 handsome lofty tree, attaining a height 

 of over 100 feet, bearing large lanceolate 

 trifoliate leaves. It is a native of 

 Brazil and British Guiana, and was intro- 

 duced to Peradeniya in 1891. Here 

 the tree grows luxuriantly, and for the 

 last two years has flowered freely, so 

 that it may be expected to set fruit at 



any time. The remarkable globular fruit 

 is of the size of a child's head, consisting 

 of a brown woody shell, which when ripe 

 contains four large kidney-shaped seeds. 

 Each of these also is enclosed in a hard 

 reddish shell, about four times the size 

 of a Brazil-nut, and considerable force is 

 required to break one open. The kernel 

 has a pleasant nutty taste, and is 

 esteemed in England for confectionery 

 and fruitarian dishes. Sonari nuts are 

 imported into England from South 

 America, and may usually be seen in 

 Covent Garden, "or retailed in London 

 at 3d. to id. each. The tree thrives best 

 in rich deep or alluvial soil. It is un- 

 fortunate thao it takes so long to come 

 into bearing, but it is a way many 

 tropical trees have. (See Frontispiece.) 



H. P. M. 



KATURU MURUNGA. 



This remarkable vegetable is a small, 

 quick-growing leguminous tree, known 

 to botanists as Sesbania grandiflora, and 

 to the Sinhalese as l< Katuru-murunga." 

 Both the tender leaves and flowers are 

 used as a choice vegetable, the large 

 fleshy petals of the latter being especially 

 relished when fried, or used in soups or 

 curries. The bark, leaves and flowers 

 are also valued medicinally. The tree is 

 known to the Tamils as " Agatti-keerai," 

 It is easily propagated by seed. 



H. F. M. 



TIMBERS. 



PRESERVATION OP TIMBER. 



(Prom the Journal of the Board of 

 Agriculture, Vol. XVIII., No. 10, 

 January, 1912.) 



The increase in the durability of 

 timber which may be brought about by 

 the use of preservatives is a question of 

 considerable importance in the United 

 States in view of the large annual pro- 

 duction of timber in that country, and 

 the subject has engaged the attention 

 of the Forest Service of the Department 

 of Agriculture since 1902. Although the 

 experiments carried out by the Forest 

 Service were confined to the treatment 

 of poles for telegraph and telephone 

 purposes, many of the results are of 

 interest to the English agriculturist 

 from the point of view of estate 

 management. 



Seasoning of Timber. — The question of 

 seasoning necessarily requires consider- 

 ation before the use of" preservatives 

 28 



is dealt with, since proper seasoning not 

 only prepares timber to receive the 

 preservative treatment, but under cer- 

 tain conditions may be in itself a means 

 of increasing its durability. 



Contrary to general opinion, the Forest 

 Service found the shrinkage taking 

 place during the seasoning of poles to 

 be very slight, amounting, in seasoning 

 from green to air-dry condition, to 

 about 0'1 in 0"2 in. in the circumference 

 at the butt end, and from 1"15 in to 25 

 in, in the circumference at the top end 

 of poles. The loss in weight during 

 such seasoning was found to be ordin- 

 arily from 16 to 30 per cent, of the origi- 

 nal weight, but in the case of yeliow 

 pine of the western United States as 

 much as 49 per cent, was lost during 

 seasoning in from three to nine months. 



The rate at which wood seasons was 

 found to depend chiefly on climatic con- 

 ditions, timber cut during spring and 

 summer becoming seasoned, as a rule, 



