3o6 



THE TROPICAL AGRICULTURIST. 



[October i, 1882. 



on the Alligator and Liverpool Rivers as a sour stiff 

 clay — Op. eit. I., pp. 104 c/ 259. Stokes says, "While 

 the banks [of the upper part of the tidal portion of 

 the Adelaide] were low — a cii'cnmstance very favour 

 able for irrigation and the cultivation of rice.' — Op. 

 cit. I., p. 415. Jukes \\Tite3. "That rice might prob 

 ably be raised in small quantities on the borders of 

 the lagoons." — Op. cit., p. 361. I have reproduced 

 these observations because they have reference to jior- 

 tions of the Northern Territory with which I am un- 

 acquainted. The meteorological phenomena, which 

 must have a depreciating influence on the value of 

 certain soils for particular crops, are — (1) The inter- 

 mittent character of the rainfall at the chief period 

 of growth. Many successive days of unclouded sky 

 and hot winds during the wet season must have a 

 deterrent effect on the growth of succulent plants and 

 shallow rooting annuals in particular. (2) The rapid 

 diminution in the amount of rainfall, proceeding in 

 a southerly du-ection thus starting with a yearly aver- 

 age of 76'89 inches at Southport. it gradually decreases 

 at the rate of about one inch to every five miles, to 

 39 '23 at Pine Creek. (This will be seen on a refer- 

 ence to Mr. Todd's reports. ) The productions of tlie 

 soil of the Government Gardens at Fannie Bay, re- 

 claimed from a dense jungle, afford evidence that a 

 great variety of useful plants may be successfully growai 

 under similar conditions of soil and situation. But, 

 as I have just shown, the climatic conditions change 

 so rapidly as we recede from the coast that I am 

 dubious, even other things being the same, whether 

 equal results will be gained in the more inland tracts. 

 If we turn our attention to the dominant vegetation 

 we find that it implies, if not sterility of soil, then 

 certainly the absence of those points of cliaracter in- 

 dicative of permanency of atmospheric moisture, and 

 conversely general exposure to the sun. Thus we 

 note the alsence of dense lofty forests, scarcity of 

 ferns and epiphytic orchids, no b'chens, no liverworts, 

 and only four species of mosses having a very limited 

 range of distribution. However, I believe that in 

 several parts of the colony various species of Gossy- 

 pium [cotton-plant), rice, and indigo could be cultivated, 

 and a fair or even prolific crop obtained. Indeed, 

 good cotton has been produced witliin the Murray basin 

 (see F. von Mueller, "Select Plants for Cultivation," 

 p. 99, 1876). The rice-plant is indigenous to the North- 

 ern Territoiy, having been found by Baron F. von 

 Mueller in the marshes about Hooker's Creek, by Mr. 

 AVilson in the marshes of the valley of the Norton- 

 Shaw River, and by Mr. J. A. Giles in the valley of 

 the Birdum Creek. The tamarind is also a native, 

 having been noticed first by Leichardt at Port Essing- 

 ton and suljsequently by Mueller on the cliffs at the 

 entrance to the Victoria River. Another useful plant 

 indigenous to the country has been overlooked. It is 

 Tacca pinnatifida, from the tubers of which the main 

 supply of the Fiji arrowroot is prepared. I noticed it 

 growing in rather humid gravelly soil here and there 

 from Palmerston to Pine Creek. 



We think it quite probable that a good deal of land 

 with a suitable climate is avilable near the coast, if 

 only the labom- difficulty can be overcome. 



THE RAINFALL OF THE GLOBE. 



Nature reviews, in an interesting and, no doubt, 

 scientifically correct fashion, a paper recently published 

 on this subject by Professor Loomis of America. There 

 is so much of value to Ceylon readers, and especially 

 to those who take an interest in the causes of de- 

 ficient rainfall that we make the following extracts : — 



Leaving out of cousidiration all exceptionally heavy 

 rainfalls, confined to limited spots, such as those of 

 Cheerapunji, in Assam, which amounts to 492 inches 



iinnually, and the Stye, in Cumberland, which is 

 about 190 inches, the hoariest lamfall is r.i>-t with 

 in the rain. belt, which .surrounds nearly the whole 

 globe, lying between the northeast and somh-east 

 trade winds. Absolutely the largest lainfnlls over 

 hirge regions are to be found wliere the trade- winds 

 nfter having traversed a great breadth of ocean, are 

 forced against and over a breadth of land of some 

 elevation and extent which lie across their path. Of 

 these the best exa'iiples are the highlands of Java, 

 Sumatra, and Assam, in the Old World, and par's 

 of the north of South America, nnd of the steep 

 slopes of Mexico facing the Gult of Mexico in the 

 Aew World, over which the trades or monsoons dis- 

 charge their moisture so copiously as to raise the 

 rainfall over large tracts up lo nnd in cases consid- 

 erably above 200 inches annually. The influence of 

 lieight is well illustrated by the ra nfall of Mauritius ; 

 thus, whde at the observatory it is 46 inches, it 

 amounts at Cluny to 149 inches on a mean of the 

 sime 19 years. Similarly in St. Helena, while near 

 the sea level it is only 5 inches, at a height of 1,764 

 feet it is 48 inches. In Ascension no part of which 

 rises to any considerable height, the aunual rainfall 

 is only 3 iuche.s, and the whole island is little else 

 than a burned-up desert. The rainfall is particularly 

 large in mountainous regions iu both hemispheres 

 above lat 40°, situated on the eastern shores of the 

 great oceans, and contequeutly in the full sweep of 

 the stionj; westerly winds of these high latitudes. 

 Thus large poitions of Scotland north of the Clyde, 

 one or two small patches in England, a few spots 

 in Ireland, large tracts lje;ween California and Ala-ka, 

 the south of Chili, and the west coast of the south 

 island of New Zealand have an annual rainfall ex- 

 ceeding 80 inches. Nay even at Ber;;en, lat 60" 23' 

 N., bathed in the warm, moist westeily wmde of the 

 Atlantic, the rainfall is 73 inches annually, which i» 

 the largest rainfall yet observed any where at so 

 high a latitude. Those headlands, even though of 

 comparatively small height, which run out into the 

 sea, meeting the moist oceanic winds, have rainfalls 

 very considerably above the average — u«ing doubtless 

 largely lo the greater friction of land than water on 

 the winds, thus purtially arresting their progress, and 

 inducing a more copious precipitati"n. As causes of 

 deficient rainfall, Professor Loomis enum rates five, 

 viz : — (1) ft uniform direction of the winds during 

 the year, such as prevails within the regions of the 

 trades, illustrated by the rainfall of Ascension, Sahara 

 and South Caliiornin; (2) the prevailing wind having 

 crossed a mountain range, thence descends on the 

 l^eside, illustrated by the desert of Gobi, Chili and 

 large tracts in Spain ; (3) ranges of mountains so 

 high as to obstruct the free movement of the sur- 

 face-winds towards the interior, as parts of Central 

 Asia and California ; (4) remoteuess from the ocean 

 measured in the directiou from which the wind pro- 

 ceeds, illustrated by the gradual diminution of ihe 

 rainfall on advancing eastward int" Europe ; and (5) 

 high latitudes, since beyond lat. 60°, at a little dis- 

 tance from the ocean, it seldom exceeds 10 inches, 

 and there are appirenily large tracts in North America 

 and Asia where the rainfall is less than 10 inches. 

 As regards this last statement, observation scareely 

 bears it out, since in the Europe- Asiatic coutin- 

 ent,only two stations iu latimde above 60', viz., 

 Kolft iu Russian Finland on the Arctic Sea 

 •and Yakutsk show rainfalls less than 10 inches, 

 and these are doubtful owing to the short periods 

 oTcr which the ob-servations ext nd. 'Ihe truth 

 is there are other causes powei fully influencing the 

 distribution of the rainfall, than these whicli an 

 examination of the rainfall of the individual 

 months, notably January and July, best disclosis. 

 These causes have their explanation ia the sys- 



