Malayan Agricultural Journal, Vol.14, No.5
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THE Malayan Agricultural Journal. Vol. XIV.] MAY, 1926. [No. 5. OBITUARY. With deep regret we have to record the death of Inche' Mohamed Zain bin Mohamed Jianiff, Junior Agricultural Assistant, Butterworth, which occurred in Penang on April 27th, 1926. 105 Original from and digitized by National University of Singapore Libraries 10G MALAYAN GUANO DEPOSITS. V. Gkeenstreet. Pliosphatic deposits occur in caves in limestone hills in various parts of Malaya, extending' also through Siam and into the Shan States. The mammal value of these deposits has long heen recognised by the cultivators of padi, parti¬ cularly in Kedah and Perlis where there is close proximity between cave and bendang. Although the origin of the phosphatic element has been attributed to the original lime¬ stone rock(l) analyses of samples of limestone have failed to reveal its presence. There is little doubt therefore but that the deposits have a common origin in the excrement and dead bodies of bats. In those caves which still contain vast numbers of bats there is a constant rain of excrement which, when quite fresh and sticky is remarkable for its high nitrate content,(2) a fact which was exploited as far back as 1876 when fresh bat-guano was used for the manufacture of saltpetre. The nitrate content very rapidly diminishes and combination of the excrement with limestone usually produces a substance possessing only a low nitrogen content. The variety of forms which this phosphatic material presents is very great, varying from entirely amorphous to nearly completely crystalline, from a texture almost homogeneous to forms with over 50 per cent pore space and in colour from black through brown, red and yellow to nearly white. As with the exception of that of the author(3) there appear to be only two published analyses(4) of Malayan phosphates this article has been written in order to place on record +he results of analyses carried out during the last five years. The analyses of Batu Caves guano, samples number 1, 2 and 3, of Batu Kurau guano and Kampong Reman guano were carried out by Mr. (J. 1). Y. Georgi, the remainder by the author assisted by Inche Abdul Majid. It lias been found convenient to group the deposits according to the State in which they occur. SELANGOR. The principal Selangor deposits occur in the Batu Caves while there is an insignificant deposit in a granite cave at the Gap. The composition, which is given in table 1, shows that, although Batu Caves guano is in no instance of high quality, the phosphoric acid and nitric acid content decrease rapidly with the depth of the strata. (0 T-\ G. Willbourn. Journal Straits Branch. Royal Asiatic Society 19-22.86.237 (2) W. F,. Maxwell. Journal Straits Branch, Boyal Asiatic Society 1892.103. W. B. D'almeida. Journal Royal Geographical Society, 187(1. (3) The Composition of Kedah and Perlis phosphates. Malayan Agricultural Journal 1923.11.70. (4) Jj. Wray. Perak Museum Notes 1.1892.72. A. Voelker. Bat Guano. 1878. Original from and digitized by National University of Singapore Libraries 107 Table 1. Ppvcmitafff composition of guano from Batu Oaves and the Gup. Batu Caves'Batu Caves Batu Caves Batu Caves 1 3 4 Sample Sample Description of Sample. Surface from from Bulked Gap. sample depth depth of 4ft sample of 2ft. 1922. 1922. 1925 1 <122. Moisture 6.0 0.8 21.6 3.4 11.4 Loss on ignition - 5.7 1 9.0 23.2 18.4 Nitrogen (Nitric) - 0.55 . nil. nil. Nitrogen (Aimnoniacal and organic) 0.42 0.21 0.3S 1.1 0.97 0.21 Nitrogen (Total) - 0.38 0.72 Phosphoric Acid (R 0„) 11.25 2.50 3.56 ,10.20 2.05 Equivalent to tri- calcium phosphate (Ca;!P2Oa) 24.6 5.5 7.8 22.2 4.5 PERAK. There are numerous limestone hills containing caves in the neighbourhood of Ipoli but only one sample of guano, from (xunong Tunggal, has been received for analysis; the depth to which the sample was taken is unknown. A deposit of insignificant value occurs at Batu Kurau in the Lurut district. The composition of these samples is shown in table 2. Table 2. Percentage composition of guano from Gunong Tunggal and Batu Kurau. Gunong Tunggal Batu Kurau Description of Sample. Kinta. Larut. Moisture 8.5 21.3 Loss on ignition 20.7 26.7 Nitrogen (Total) 0.5 1.5 Phosphoric Acid (P, 06) 5.7 0.5 Equivalent to tricalcium phosphate (Ca3 P, Os) 12.4 1.2 Original from and digitized by National University of Singapore Libraries 108 A limestone cave at Gunong Pondok, Padang Pen gas contains probably the richest guano in the country. The limestone rock which at the entrance to the cave consists largely of crystalline calcite becomes more and more amor¬ phous as it comes into contact with the bat-excrement in the interior until it finally loses its crystalline character entirely. In some strata'the rock is changed to a soft, pale- yellow powder while in others it is semi-crystalline and cellular. The floor of the mouth of the cave consists to a considerable depth of earthy, chocolate-coloured matter. The cave, which is approximately twenty-five feet wide by six hundred feet deep, contains vast numbers of bats and in consequence there is a continuous deposition of excrement. Twenty-four samples of guano from various depths through¬ out the cave have been analysed and the results are shown in table 3. Original from and digitized by National University of Singapore Libraries rock. Soft 1.(5 12 18.5 14.8 14.5 31.(5 Powder. Yellaw 8.7 11 19.2 nil. 30.0 05.5 CJ 10 o 21.7 22.0 nil. 15.0 32.8 . 3% 9 5.8 S M7 1(1.1 nil. 31.0 07.7 o o o 8 ai 10.3 41.7 1.1 15.0 32.8 Powder. Black i 15.(5 25.8 nil. 24.0 52.4 Powder. 7.0 Brown Dark 10.0 29.1 18.0 39.3 Powder. Yellow 5 19.7 13.8 nil. 23.0 50.2 4 9.4 35.2 nil. 19.0 41.5 Tatslu3. S'1 o O 8 Cj 1.8 t-" CD 13.5 21.7 24.0 52.4 1 C £ 2 2.1 CD 15.8 4G.3 12.0 2G.2 3 c o 5.5 1 1.9 fromPi'rcenhtrePondok.Gunongcompositionguanoof CM IS.9 55.S 12.0 Sample.Descriptionof Samplenumber. Moisture ignitionLosson (Nitric)Nitrogen (P205)Phosphoricacid Equivalenttricalciumtophosphate (.<VP,Ds> Original from and digitized by National University of Singapore Libraries Original from and digitized by National University of Singapore Libraries Singapore of University National by digitized and from Original • V-fi V-H ^ _ 2. §" ^ w 'bb £. ~ §' ry3 !? 5. c/q 2 ^ ^ rf Sample. g of P ST § s- 9 <g Description P^ 'M 2". p.* o 0 £2 ° f-1- 3. = c — ✓--N • £"* ? 1 —J c & *H- 2 o rn ^ ro !? 1 1 1 1 1 -1 CO « 7 -: 7 rock. Soft 7 7 CO CO _ _ 2-" P' CO 2J Hard rock. ri 4- Hard rock. p b g F b c H « *>5 3 M E5 H. c» w H: »- rock. Hard H. s * b ic b CO 2 B. Rock crystals. - I ^ b' S ^ 4^ Brown Powder. X ic * b b b -1 CO — x ?' b x — Grey Powder. s O b b b co o 4- b b b ~ PC Powder. Brown b • V ic b , [jf ,c b /-\ »c Fresh and sticky. 4- 1-i 4- Very fresh and IC —• 4- 05 >C IC sticky. b b b b re • c o 1C CO p Black Powder. CO " CO b b o ~ 0» u-1 Ct CO Metamorphic to 4- limestone. 4~ b b OH m These figures show,, that Gunong Pondok guano con¬ tains an average of 20 per cent phosphoric acid, that fresh samples contain an average of more than 7 per cent of nitric acid (calculated on a moisture-free basis) and 13 to 18 pei cent in extreme cases. An interesting feature is ihat in some cases the underlying rock has been changed by the layer of excrement into calcium phosphate as a pseudomorph of the original oaleite. Samples from a depth of 8 feet were found to contain 20 per cent of phosphoric acid below which no excavation was made. PATIANG. Samples of only one Pahang guano deposit have been received for analysis. This deposit occurs in limestone caves at Kampong Raman, Kuantan. The rock containing the caves is reputed to cover 100 acres of land and the guano deposits to be considerable. Table 4 shows the composition of 2 samples of Kampong Reman guano both taken from a depth of (i feet. Table 4. Percmhuje composition of gwmo from Kumponj Reman. Description of Sample. dark coloured, light coloured. Moisture J 8.1) 25.3 Loss on ignition 22.1 22.3 Nitrogen (Total) (). i 8 0.41 Phosphoric acid (IG05) 4.7 3.2 Equivalent to tricalciuni phosphate (Oa,PsO.) 10.8 11.4 PERLIS. The small Fnfederated State of Porlis possesses by far the richest of the known guano deposits. There are repined to be over one hundred guano bearing caves within an area of two to three square miles, while the total amount of the guano lias been variously estimated at from fifty thousand to one million tons. A cave in Bukit Ketri was worked out many years ago by a Dutch Company which exported the guano to Sumatra.