230 



TROPICAL AGRICULTURE 



CHAP. 



Grows wild 

 in the West 

 Indies. 



History of 

 the plant. 



The use of 

 the oil. 



Its value a 

 a lamp oil. 



be said to be cultivated, for it grows spontaneously on most 

 waste lands, and in some places it is a troublesome weed. 

 The valuable properties of the plant were known in very- 

 ancient times, and seeds have been found in tombs in Egypt 

 supposed to have been 4,000 years old. The oil was used 

 by the Greeks and the Romans, and the plant is believed by 

 some authorities to be the gourd mentioned in the Scriptures. 

 The Romans, seeing a resemblance between the seed and 

 the unpleasant insect now known as a tick, called both 

 Riciiius^ and this Latin name has been adopted by botanists 

 present to indicate the genus of the present plant. 



The oil has been used from time immemorial as a purgative 

 medicine, and for lighting purposes ; and, recently, it has 

 been largely employed as a lubricant for machinery, watches, 

 clocks, (S:c., and for the making of soaps, pomatum, and per- 

 fumed oils. It is one of the best and safest lamp oils known. 

 It burns slowly and thus effects a saving, it gives a good 

 white light, it is free from danger, and it gives very little soot. 

 Owing to these advantages, it is used for lamps on all 

 the Indian railways. The cold drawn oil gives the best 

 light; indeed, one authority states that "no other oil can 

 vie with this light, it being almost electrical in its 

 brilliancy." 



Wide range 

 of climate. 



The best 

 soil. 



The ex- 

 planation of 

 an error. 



Soil and Climate.— The plant is a hardy one, and it 

 will stand a wide range of climate. In the tropics it grows 

 from the sea level to a height of 5,000 feet, and it will thrive 

 in the summer time in England and the Northern States of 

 America. In temperate climates, however, the plant is an 

 annual, whilst in the tropics it becomes a small perennial 

 tree, attaining sometimes to a height of from twenty to thirty 

 feet. The best soil is a rich, well-drained sandy or clayey 

 loam ; and light loose sandy and wet heavy soils must be 

 avoided. It is said to improve the richness of soils on which 

 it is grown ; but this is an error, for the seeds contain much 

 nitrogen, potash and phosphoric acid, and thus heavy crops 



