550 



THE TROPICAL AGRICULTURIST. 



[January i, 1883. 



or counting, as I have just done, the rupee at two shill- 

 ings, the unavoidable rate again ere long, rupees 53-10 

 nelt per acre, — not a bad result for a kind of cultivation 

 winch apparently would give little trouble and run fewer 

 risks than any other kind. I have taken no account of 

 the probable great improvement in the yield which a care- 

 ful husbandry would secure. 



Of risks, the only one I see would be at the reaping 

 tinif to avoid losing the seed, either by too rough a 

 handling or by allowing the trees to stand too long after 

 the ripening had begun. Then the bagging should take 

 place as rapidly as possible, or small insects will get in and 

 bore the seeds and thus depreciate their worth. 



But even in the case of Danjive becoming popular, I do 

 not believe that either coffee, " divine coffee " as Voltaire, 

 and .ifter him all Frenchmen called or call it, or tea, 

 another *' Celestial" beverage, need fear a new rival. As 

 tonic, nutritive, nerve-bracing and brain-feeding drinks, 

 coffee and tea will always stand at the head of all other 

 drinks. Yet, for certain purposes, Danjioe may become a 

 beneficient drink too. Even then it will not more injure 

 coffee or tea than Khine wine does champagne or Chateau 

 Margaux. Ikeawaddy. 



Myan-Oung, British Burmah. 



THE POTATO DISEASE. 



The somewhat novel facts made known by Mr. A. S. 

 Wilson with respect to the Potato disease are such that 

 only scientists may venture to dispute the correctness of. 

 Accepting them as exact, I thiuk it gives some clue to 

 that difficult point, which has always bothered those who 

 have closely observed the action of the disease in the 

 Potato plant to understand. How often has it not been 

 mentioned that the fungus manifests activity almost in- 

 variably first in kinds of Potatoes that are approaching 

 maturity, and this it has j^uzzled us exceedingly to ex- 

 plain. We have naturally thought that, with a sporadic 

 attack simultaneously all over a breadth of early and late 

 kinds, the tenderer leafage should first show eviflences of 

 the disease, but almost always the more mature kinds, 

 those having the firmer leafage, have suffered first. We 

 must now conclude, as Mr. Wilson has shown us the fungus 

 really generates itself [Frequently, whether universally has 

 yet to be proven. — Ed.] in the leafage, that it as well as 

 the plant requires a certain time equally to matiu'e ere 

 the one ripens and the other can exhibit external deve- 

 lopment. In his reference to the resisting powers of the 

 Cliampii'U Potato — powers, by-the-bj'e, always more strongly 

 seen in Magnum Bonum — Mr. Wilson gives support to the 

 opiiu'on I long since put forth, that the disease-resisting 

 power of certain kinds of Potatoes was mainly due to 

 the very hard woody nature of the stems, the which 

 checked the fungus in its operations. None the less we 

 must not overlook the fact that whilst for several years 

 past the disease has eventually totally destroyed the leaves 

 and stems on many hundred acres of Magnum Bonum, 

 yet the tubers have apparently remained sound, so that 

 it is evident some other causes as well as the one thus 

 suggested have been in operation to save the tubers. ]Mr. 

 Hibberd not long since made the suggestion that all kinds 

 having erect growing tojis were less liable to the disease 

 than were those which have spreading sprawling tops. 

 That is no doubt correct, but it does not clear up the 

 case except on the before-mentioned hypothesis, that the 

 stems as well as being erect were hard and woody. This 

 hypothesis is again based upon the curiously received 

 notion that the fungus, let it attack the plant at the first 

 how it may, travels down the internal structure of the 

 stems into the tubers aud causes decay and rot. It is 

 therefore very remarkable that whilst Mr. Wilson should 

 be putting forth his new discoveries as to the life-history 

 of the Potato fungus, Mr. Jensen should be putting iu a 

 claim as to an important discovery that seems to run 

 quite counter to Mr. Wilson's views. Mr. Jensen sets no 

 store by the internal operating theory but holds that the 

 real work of the fungus in producing disease in the tubers is 

 the product of external action. There need not., however, 

 be any considerable diversity between views that we may 

 dc ni so opposite. Mr. .Ten.sen has assumed that the fun- 

 goid .spores were borne on the air, deposited on the leaves 

 of the plants aud on the soil, and thence washed by rains 



into the tubers if not protected by a thick covering of 

 soil. But if, as Mr. Wilson, as I understand him— for 

 fungoid jargon is somewhat barbaric— shows that instead 

 of the spores falling upon the surface of the leaves from 

 the air they are really begat in the leaf itself and pre- 

 sently burst through the leaf cuticle into its external sur- 

 face, then exactly the same result occurs as if the other 

 thing happened, for the spores are there to be washed 

 into the soil. It therefore does not conflict with or detract 

 from the value of the system of protective earthing which 

 Mr. Jensen puts forth. No one has ventured to dispute 

 the theory as to the operation of the Peronospora spores 

 on the young tender-skinned tubers, and it would be diffi- 

 cult to disprove; whilst the past season has furnished 

 myriads of examples where the fungus had entered the 

 skin of the tubers, making a pock-like dark blotch, and 

 that was all. Evidences of this sort have been far more 

 abundant than have those favouring the entry of the fungus 

 into the tuber through the stem. The very interesting 

 mention of the quick operation of the fungus upon cut 

 or bruised tubers has, too, had myriads of examples. The 

 common idea in connection with the di-y rot or decay 

 that would follow upon a cut or bruise made with the 

 fork iu lifting was that the blow had destroyed a portion 

 of the cellular tissue, hence the decay, The theory pro- 

 pounded by Mr. Jensen is far more probable, aud its 

 truth can hardly be doubted. But when we again turn 

 to the so-called disease-resisting kinds, we find that the 

 tubers of these as a rule are not more deeply buried than 

 are those of kinds that do readily take the disease, and 

 therefore we can but assume either, as previously pro- 

 pounded, that the stiff', erect growers — probably because 

 the foliage protects the soil beneath from rain— are thus 

 disease-resisting, or else their tubers have stouter skins, 

 which renders them the more impregnable. I do not un- 

 derstand Mr. Wilson to suggest how the fungus spores 

 first get in<o the foliage, whether they hybernate in the 

 soil during the winter and are taken up by the plant in 

 the spring, or whether they are in the seed tubers and 

 developed from them. No doubt much is to be learnt yet 

 respecting this singular and destructive disease. — A. D. 

 [It will probably be found, judging by the analogy of 

 other fungi, that all these observers are right from their 

 own point of view— the di.screpancies being accounted for 

 by the varying habit of the fungus. — Ed.] — Gardeners' 

 Chronicle. 



CASTOE PLANTING. 



TO THE EDITOR OF THE " INDIAN AGRICCLTURIST." 



Sir, — Some time ago there appeared in the Statesman 

 a little letter on a large subject — a query or two as to 

 tlie cultivation of the castor plant. Numbers in common 

 with your correspondent have had stray thoughts directed 

 to this enterprise, and some have wondered why large 

 castor factories, with oil-presses, have not dotted the land 

 of Ind; for the pLant is easy and inexpensive to cultiv- 

 ate, and lucrative beyond dreams. Were this commodity 

 (castor seed) procurable in large quantities, there is no 

 question but it would supersede coal as a gas yielding 

 product. The light would be infinitely superior, and the 

 atmosphere would be free from the deleterious properties 

 with which, in cities, the use of g.is charges the air we 

 breathe, and consequently the lungs. Take a simple castor 

 seed,_ hold it over a light, and when it slightly cracks, 

 gas is emitted, and this burns for the space of two or 

 three minutes in a beautiful white steady glow greatly 

 resunbling the electric. There are altogether some eleven 

 varieties of this species, and the savants have endowed 

 all and each with scientific designations. They fructify 

 plentifully even in the most louely soils. I send you three 

 samples of the seed grown in these parts. The smallest 

 kind is said to yield the most oil, but the difference is 

 not much, as I infer from the small difference (one anna 

 per maund) iu price. It is grown here exten,sively as a 

 field crop, and is an annual. The land for it must bo 

 well prepared (ploughed), although its quality may be in- 

 different. It is sown in August aud September, when the 

 heavy rains have passed, for it perishes with an abund- 

 ance of water. The seed is put down in the furrows of 

 the plough six inches deep aud two feet apart. No man- 

 ure is used, and when the plants are a span high the 



