December i, 1884] 



THE TROPICAL AGRICULTURIST 



463 



plant they found the leaves and branches of a neighboring 

 plant touching the banana, by which they were enabled to 

 descend to the ground. 



Insects on growing plants have been placed in a closet and 

 under glass covers, and subjected to the odors of the gas ; 

 the insects were destroyed, particularly aphides. 



On one occasion I removed a geranium with the earth 

 attached from its pot, and cut abcut an inch of the earth 

 and roots from it. A corresponding amount of pure naphthal- 

 ine was put into the earthen pot and the plant replaced. A 

 quantity of naphthaline was also placed on the surface of the 

 pot, and watered in the usual way for a period of several 

 .lays, but no evil effects were observed on the plant. In this 

 experiment two earth-worms were found dead outside the 

 pot, the odors having driven them from their abode. 



About twelve months ago a quantity of peas was received 

 at the Department of Agriculture. They were found to be 

 half eaten and swarming with small beetles. I placed a pint 

 of these peas in a jar with a small portion of naphthaline, 

 which quickly destroyed the insects. 



A few days ago I had planted in the hot-house of the 

 Department of Agriculture a portion of this same lot. They 

 are in healthy growth, showing that the germs were not many 

 way injured, although confined for twelve months in this gas. 



On last Saturday I placed these three tender plants in an 

 atmosphere of naphthaline, and kept them in that state for 

 a period of thirty-six hours, being thirty-five hours longer 

 than was necessary for the destruction of minute insects. I 

 observe that a single leaf on two of these plants has wilted. 

 The third is wholly unaffected. 



Since the above experiments were made I have subjected a 

 youug carp about four inches in length to the action of naph- 

 thaline, byplacingan ounce of the drug in about two gallons of 

 water, in which the fish was swimming. For a period of ten 

 hours the fish was seemingly unaffected. On the following 

 morning it was found floating on the surface dead. The 

 cornea of both its eyes had become of whitish translucent 

 color ; otherwise no peculiarity was observed. 



[Read at the fifty-fourth regular meeting of the Biolog- 

 ical Society of Washington, December 28th, 1883, held in 

 the U. S. National Museum.]— Gardeners' Monthly. 



COCONUT-PLANTING : 



AS PRACTISED IN THE LOWCOUNTRY OF CEYLON. 



To resume,* the calculation of proceeds of a coconut 

 plantation according to the Goiya system was last touched 

 upon. The next paragraph gives "another sketch of a 

 plantation that was cleared and planted and allowed to 

 grow into jungle for 12 months. At the end of that 

 period the jungle was " 10 feet high," with all the plants, 

 less four, destroyed by wild pigs. One can but conjecture 

 the damage done, as the acreage of the plantation is not 

 given. The proprietor of this plantation, we are told, had 

 much pluck and went to work the next year on a new 

 system. He rooted out all the jungle at an expense of 

 R20 the acre, and planted the land with manioc. The 

 wild pigs fancied the manioc more than the coconut plants, 

 and about 70 per cent were saved. The vacancies were 

 supplied twice a year, yet at the end of nine years they 

 amounted to 10 per cent. During all these years the place 

 was kept in order, and the pasturage was rich. At the 

 end of the fourth year cattle were put on the plantation, 

 but securely tethered against damaging the coconut plants. 

 Before the place was five years old, 10 per cent of the 

 plants had commenced to bear, and seventy-five per cent 

 of the plants treated with cattle manure were in bearing 

 before the ninth year ; its further progress cannot be stated, 

 as the place has not gone beyond the ninth year. The 

 trees, we are told, that had commenced to bear three 

 years ago will, allowing for all contingencies, yield on an 

 average 80 nuts per tree, or 5,600 the acre, which at R30 

 the thousand, will give the handsome return of R180. The 

 lucky proprietor of this model plantation, we are told, will 

 not wish it to be known that he has spent over R200 the 

 acre on the place, without the further fact receiving 

 publicity, that by the end of the twelth year he expects 

 the yield to cover every penny of principal and interest, 

 and give him a very valuable property besides. To which 

 I may be allowed to add, that the proprietor must be a 

 very sauguiue man indeed, to calculate yield three years 



* See T. A., p. 375. 



hence with such confidence and nicety. Instinct points 

 to the writer of the essay, who never allows the small 

 qualifying word "about" to disturb his calculations, and 

 to this sanguine proprietor, as one and the same person. 

 The only manure applied to the property was one-third 

 of a ton of quick lime at a cost of R7"50. The high ex- 

 penditure was owing to every work being experimental and 

 the soil being rich, which of necessity made weeding, &c, 

 heavy. A portion of this property, which received similar 

 treatment to the rest, but did not receive any cattle 

 manure, is so backward in growth as not to show even 

 stem as yet. This, to me, does not speak much for the 

 soil. Fancy trees nine years old not shewing stem as yet ! 

 But they are to receive yearly doses of poonac till they 

 come up to the forward plants. 



We are next told how an old plantation 21 years old 

 and with a poor sandy soil was treated, and how it re- 

 sponded to the treatment. The largest crop it had given 

 was at the period named, and it averaged 13^ nuts per 

 tree. A new manager assumed charge at this period, and 

 submitted a scheme which added 10 per cent to the an- 

 nual expenditure. It was at first opposed, but finally al- 

 lowed. As a first step all the pigs were disposed of, as 

 also one-third of the cattle. The rest were allowed free 

 access to the poonac tabs, and had a roomy shed allowed 

 them, which was daily littered with jungle stuff and ferns 

 from the low grounds ou the estate. When the rains 

 commenced, all the manure that had accumulated was 

 carted and spread on the surface of the ground at the 

 rate of 2i cubic feet to each tree, and dug in with mamo- 

 ties. Not much could be dome in this way, as it would 

 have taken 12 years to go the round of the estate, while 

 the effects of the manure last only three years ; but, as 

 a result, the average yield per tree went up to 21 nuts 

 in six years. Steamed bones were next used, of which 

 two tons were allowed annually, with the result of the 

 yield running up to 33^ nuts per tree in the eleventh year. 

 The estate next fell into the hands of natives, who allowed 

 the yield to fall to 12 nuts per tree. The whole cost of 

 manuring during the 18 years was Rl per tree, and the 

 result over R3, giving a return of 300 per cent on the outlay. 

 We are authoritatively told that if five times the amount 

 had been expended, the results would have been proportionate # 

 The next paragraph is a small lecture on Chemistry, 

 and tells us that the writer looks upon the coconut tree 

 " as a chemical apparatus for turning carbon, oxygen and 

 hydrogen into oil." Plants draw the whole supply of 

 these elements from the air, therefore no quantity of 

 oil removed from a given area of land impoverishes the 

 soil. But to make oil, the coconut tree must needs grow, 

 and to grow it draws from the soil nitrates, phosphates 

 and alkalies. If oil only is removed from a land, and all 

 the other products of the coconut tree returned to it, the 

 average yield of oil will never decrease as long as the tree 

 is in health. Introduce outside supplies of nitrates, phos- 

 phates and alkalies, and the yield of oil will increase and 

 the soil be improved. I trust your readers appreciate this 

 little, simple lecture. 



We are next told to " replace fertility removed," which 

 is very good and sensible advice, but the process of calc- 

 ulation is not so easy as one could wish. " Ascertain the 

 average of the fertilizing elements removed in a given 

 number of nuts and set aside such proportion of the price 

 as will replace them." Rather a difficult calculation I 

 should say. The surest way is to manufacture oil and 

 to retain the poonac, but if the crops be sold as gathered, 

 the planter must know exactly how much " nitrate, phos- 

 phate and alkalies are in a candy of copperah, and their 

 prices," so as to purchase such fertilizers for application 

 to his land. Beautiful in theory, but difficult of practice. 

 One hundred and fifty pounds of poonac. we are informed, 

 will replace the fertility removed by 1,000 nuts, so that 

 that is the cheapest and best manure for coconuts, especi- 

 ally if passed through a cow. 



The manure resulting from cattle only grazed on a land 

 does dot add to its fertility, but it is of great importance 

 that such manure should be placed at the roots of young 

 coconut plants which do not go far in search for food, 

 as aids to rapid growth and early bearing. The benefit 

 the plants will derive will not be only from the food thus 

 placed within their reach, but the roots will be stimul- 

 ated to increase their feeding ground. It is more bene- 



