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BATS' GUANO FISH GUANO 



In many limestone caves in South Africa, immense deposits occur. 

 These consist of silt, bats' excreta, bones of various animals, and often 

 of the excrement of wolves, jackals, etc. 



The deposits are of very variable composition, as is shown by 

 many analyses made by the writer. The following may be quoted 

 as examples of the valuable manurial ingredients found in various 

 samples : 



I. was a fresh bulky deposit consisting entirely of the excrement 

 of bats from the Zoutpansberg. 



II. consisted of bats' dung and silt from caves near Potchefstroom. 



III. consisted of bats' guano and silt from a large cavern at 

 Wonderfontein, near Potchefstroom. 



IV. was believed to consist mainly of wolves' dung, and was from 

 a considerable depth 8 or 10 ft. in a deposit in a cave near Won- 

 derfontein. 



V. contained many bones, from a cave at Wonderfontein. 



VI. was a recent deposit, consisting largely of the excrement of bats, 

 from a cave at Elandsfontein, near Pretoria. 



Many of these deposits contained a considerable proportion of their 

 nitrogen in the form of nitrates, and some of them contained appreci- 

 able quantities of manganese dioxide. 



Fish Manure or Fish Guano. The bodies of fish are highly nitro- 

 genous and their bones, in particular, contain large quantities of phos- 

 phates. They therefore form a valuable manure and are often used 

 whenever, through an unusual glut in the market, the price falls 

 sufficiently. - Then, too, the refuse of fish their heads, bones and 

 other offal is now manufactured into manure, especially in Norway. 

 In America the refuse from the manufacture of Menhaden oil is an 

 important manure. The flesh of whales is also used as manure. In 

 general the most objectionable ingredient in fish guano is the oil, 

 which prevents or hinders the fermentation and decay of the manure 

 by repelling water. The following table shows the average amount 

 of fertilising material in various kinds of fish manure : 



