^32 



THE TROPICAL AGRICULTURIST. 



[August i, 1885. 



$orrcspajulcnc-i.;. 



To thi Editor of tin " Ceylon Observer. " 



:MR. JOHN HUGHES OS BATS' DUNG, &c. 

 London, E.C., Sth May ISSa. 

 Dear Sir, — I send you an article on Bats' Dung 

 Oiiaiio from tbis week's .llaik Lane Express, which 

 gives some new iuterestiug information about a 

 natural deposit likely to be most valuable as manure. 

 Yon will notice tb;>t reference is made to some 

 analyses by myself, but the details are not given ; so I 

 enclose the full results of one sample, as jour readers 

 i»ay know of similar deposits in the caves of Ceylon. 

 At present moat of this Iv^ts' guano has been fouud 

 in Te.\."is, but I have had samples sent to me from 

 Jamaici, and doubtless wherever there are large caves 

 in a country with a hot climate, we may e.xpeot to 

 find these valuable accumulations of bats' dung. 



I have received yonr interesting book on " Ceylon 

 in 1SS4." It should be in the librariet of all the 

 Indian passenger steamers, for Ceylon is now becoming 

 of general interest to travellers from its central situ- 

 ation, beautiful scenery and varied productions. 

 Bats' Dung Ouano from Texas. 

 ■Water .. ... ... 14-53 



•Organic matter ... ... 47'5l) 



tl'hosphoric acid ... ... 7'30 



Lime ... ... ... 14(54 



Sulphuric acid ... ... 413 



Carbouio acid ... ... 307 



Oxide of iron ... ... '40 



Alumina ... ... ... -57 



Alkalies, magnesia, ;£c. ... 3.94 



Insoluble, siliceous matters (sand) 3-66 



Total ... 10000 



• Containing : — 



Nitrogen as organic matter 3-47 equal to ammonia 422 

 „ nitrates 267 ,. „ 3-24 



,, ammonia 1-43 ,, „ 1-79 



Total 7-62 „ „ 925 



t Equal to tribasio phosphate of lime 1594. 



JOHX HUGHES, F. c. 8. 

 [The Sinhalese are aware of the value of bats' 

 dnng and nsa it to fertilize their paddy-fields. If 

 obtainable in quantity and cheaply, it would he 

 valuable as an application to fields of tea. The long 

 article sent by Mr. Hughes from the Express is 

 gi\-en in full below.— Ed. ] 



Bats' Guaso. 



That the excrement from such small animals as bats 

 should accumulate in sufficient quantity to be workable 

 as a source of agricultural fertilisers may no doubt be 

 a surprising fact to those who learn it for the first 

 time. The well-knowuf deposits of guano in Peru 

 formed chiefly by marine birds, have long constituted a 

 material source of wealth, and the substance called, but 

 haidly correctly. - fish guano -' is also a familiar article 

 of commerce. But bats' guano is a comparatively new 

 candidate in tl-e now extensive field of artificial' fertil- 

 isers, and a few words as to its composition and mode 

 of occurrence may be of interest. Although a perfectly 

 natural product, it, of course, comes under the head of 

 " artificial " fertilisers, inasmuch as it is pim?hased and 

 brought on to the farm, instead of being produced on 

 the homestead in the ordinary routine of farm practice 

 as is the case with farmyard manure. 



The bat, as everybody knows, is a little mouselike 

 animal, provided with a lateral extension of its integu- 

 ment by means of which it propels itself bird-fashion 

 through the air. It is a true mammal — that is, it brings 

 forth its young ahve and suckles its offsprins, differing 

 ta these respects from birds. Its nearest allies are to 



be seen, not in rats and mice, which are true rodents 

 fiurnished with well-developed incisor teeth, but in the 

 moles and hedgehogs, which feed chiefly on insects and 

 grnbs, and are tlierefore called iusectivores. However 

 similiu- a bat may appe.-ir to be to a mouse, an examin- 

 ation of its teeth— always a safe zoological test— will at 

 once reveal its afliuities to such insectivorous animals 

 as the mole and the hedgehog. The bat.s that may be 

 Been flitting about in tho twilight in country districts 

 are roaming the air in search of insects for food, and 

 any one who has bandied a live bat has probably not 

 been long in discovering that the fur of these little 

 creatures is abundantly infested with objectionable insects. 

 Some exotic species of bats are fiuit-eaters. and others, 

 like the vampires of South America, are bloodsuckers, 

 frequently iuliictiug cruel wouuds on the hides of horses, 

 cattle, and other animals in their que.st for nutriment. 



In this country bats dwell under the eaves of barns 

 and other outhouses, or in some similar dark or poorly- 

 lighti d nook, their noctm-nal habits, no doubt, impelUng 

 them to seek such spots where they may slumber 

 securely during daylight. In a country not much open- 

 ed up, underground caves would naturally ott'er to bats 

 such accommodation as they seem to require, and it is 

 from such bat-haunted caves in the State of Texas that 

 bats' guano is now begiimiug to find its way in to the 

 English market. Texas is one of the most south-westtrn 

 of the United .States, its southern Injundary being 

 washed by the warm waters of the Gulf of" Mexico. 

 Here, in the counties of Uvalde aud Comal, are two 

 immense caves known as the Uvalde cave aud the Cibolo 

 cave. Underground caves of this kind are not uncommon 

 in the States one of the most celebrated being the mam- 

 moth cave of Kentucky, which extends for' more than 

 two hundred miles uuderground. Such caves have usually 

 been formed by the dissolriug away of the rock by 

 subterranean water-courses, which have eventually dis- 

 appeared, learing a record of their work in a tunuel-hke 

 excavation beneath the earths' surface. The river Jlani- 

 fold in Derbyshire pursues its course for some distance 

 tmderground, and if from some geological change this 

 river were to dry up. and \mdergroimd cave would be 

 seen to be scooped out. The Uvalde and Cibolo caves, 

 however, are remarkable for the rich deposits of bats' 

 guano they contain, which have been accumulated by 

 myriads of hats over an unknown period. Their depth 

 has been tested by boring, .-uid in some cases has been 

 found to be as much as 25 feet, while the average 

 depth is believed to be not less than six feet. In the 

 Uvalde cave the deposits are estimated to cover an 

 area of at least one square mi!e. Mr. Moreton Frewen, 

 who has visited these caves, states the Jaili/ deposits 

 from the myriads of bats which still haunt them must 

 at least run into tons. 



The oflicial report of the Commissioner of Statistics of 

 the State of Texas says, with reference to these deposits : — 

 " In the mountains there are several large caves, in 

 which are enormous quantities of the richest guano, 

 the droppings through uutold years of vast numbers of 

 bats. The guano is of a dark brown colour, about tho 

 consistence of finely-ground coffee, and is as strongly 

 impregnated with ammonia as the best Peruvian guano. 

 Chemical tests have established its great value as a 

 fertihser, and it is being removed in large quantities 

 and shipped to Eint)pe by a company organized for the 

 purpose." The caves are about eight miles from the 

 railway leadmg to Glaveston and New Orleans, at either 

 of which ports shipment may be effected for transport 

 across the ocean. 



Bats' guano possesses little or no odour, and it has 

 a pecuhar felt-hke softness when passed between the 

 fingers. A cubic foot of it weighs about 73 lb., so that 

 a ton of it would occupy rather more than one cubic 

 yard. 



As Peruvian guano is so well estabUshed, bats' guano 

 must stand or fall entirely on its merits, and it appears 

 that the few parcels which have yet fouud their way 

 into this country have been disposed of. after analysis 

 at an average price of £9 per ton, which compares 

 favourably with the price of Peruvian gu.-mo, prorided 

 the two fertihsers are equally eflicacio-as. A weU-known 

 film of guauo merchants v,-Uues it at £i 10s. per ton 



