i8 



NATURE 



[September 2, 1915 



Indian indigo, or to explain how, when that embargo 

 was withdrawn, American indigfo came to replace the 

 Indian dye in European markets. What does interest 

 us is that this American indigfo was mainly the pro- 

 duct of a fifth plant, /. suffruticosa, Brazilian indigo, 

 grown both in South America and in the West Indies, 

 and of a sixth, /. truxillensis, West Indian indigo, 

 grown both in the West Indies, where it was the 

 favourite indigo, and in Central America. The culti- 

 vation of Brazilian indigo spread more widely than 

 that of any other kind; it found its way all over 

 Polynesia, and became established in the Philippines. 

 From Manila it extended throughout Malaya, where 

 the Brazilian, Malayan, and Indian indigos were 

 grown side by side, and reached Formosa, where it 

 still competes with Malayan indigo.^ Similarly, this 

 Brazilian indigo has found its way into all parts of 

 Indo-China and into south-eastern China; in Indo- 

 China and China this American plant is the only 

 dye-yielding Indigofera yet known. In the opposite 

 direction, the Brazilian indigo spread to the African 

 coast, on the western side displacing an indigo 

 already in cultivation, on the eastern finding a place 

 alongside various Asiatic forms. It is interesting to 

 note that by neither route did Brazilian indigo ever 

 reach India. 



The area occupied by the Indigofera which yielded 

 the indigo known to the ancients extended in classical 

 times, as it does still, froni Egypt and Nubia to 

 North-West India. Immediately to the south of the 

 region in which the Egyptian indigo grows, from the 

 highlands of Abyssinia as far as Zululand, occurs a 

 seventh plant, /. arrecta. East African indigo, the 

 cultivation of which has spread east to the central 

 highlands of Madagascar and west to the coast of 

 Guinea. Along that coast, however, from Angola to 

 Senegal, this indigo at a later date was largely sup- 

 planted by Brazilian indigo. 



The circumstances which, towards the end of the 

 eighteenth century, led to a revival of the Indian 

 indigo trade lie outside the scope of this article. This 

 successful enterprise had its principal seat in the three 

 Lower Provinces of Hindustan — Bengal, Bihar, and 

 Orissa. The plant at first grown was a form of the 

 Egyptian indigo ; this was still cultivated in Bihar 

 in 1812. In Bengal and Orissa, where indigo had 

 not before been grown, this Egyptian indigo, better 

 suited to a somewhat drier climate, was soon replaced 

 by Malayan indigo. From Bengal, where the culti- 

 vation of indigo ultimately died out, the Malayan 

 plant extended into Bihar, displacing the Egyptian. 

 From Bihar this plant spread westward throughout 

 Upper India and across the Panjab to the district 

 around Multan, which eventually became a favourite 

 source of the seed for the Bihar crop. From Orissa, 

 where its cultivation likewise came to an end, the 

 Malayan plant invaded the area in South India where 

 I. tinctoria was once the staple source of the dye, 

 displacing that Indian indigo so effectually that now 

 I. tinctoria is only found in the Laccadive and the 

 Maldive Islands, and in some parts of Ceylon, where 

 the share taken in the eighteenth-century effort to 

 promote the cultivation of indigo was insignificant. 

 If, however, this Malayan plant did not reach Ceylon 

 it was taken to Senegambia, as the " Indigotier de 

 Bengal," to replace Brazilian indigo, and was 

 similarly taken to the West Indies to replace 

 I. truxillensis. 



From Senegambia the Malayan indigo has found 

 its way as far as Northern Nigeria, where it now 

 grows in company with a form which cannot be dis- 

 tinguished from the indigo once widely cultivated in 

 Southern India. Allusion has already been made to 

 the possibility that the latter form' may have origin- 



NO. 2392, VOL. 96] 



ated in Africa, but the more probable, if more prosaic, 

 explanation of its presence in Nigeria is that when 

 seed of the Malayan indigo was taken to West Africa 

 from Chandernagore in Bengal, a supply of South 

 Indian seed was also taken from Pondicherry in 

 Coromandel. But while we know that the first trans 

 action took place, wfe can as yet only surmise the 

 second. 



In the West Indies the cultivation of Malayan 

 indigo did not take root as it did in India and in 

 West Africa. The effects of the competition by India 

 had made themselves felt before the Malayan plant 

 reached the islands. Where indigo-growing was not 

 abandoned in favour of sugar and cotton, the West 

 Indian plant, which was at least as valuable as the 

 Brazilian, even if it was inferior to the Malayan one, 

 had already been displaced by an eighth species, 

 I. guatimalensis. Central American indigo. 



Although Ceylon took no part in the revival of the 

 eastern indigo trade, the Dutch East Indies did. At 

 first, as we have seen, the Indian, the Malayan, and 

 the Brazilian indigos were all grown ; later, however, 

 the Malayan plant, just as in India, displaced all other 

 kinds. But in Java a further step, never adopted in 

 India, came to be taken ; Central American indigo, 

 /. guatimalensis, was introduced, and displaced the 

 Malayan plant, /. sumatrana. Later still, yet another 

 displacement occurred ; about the middle of the nine- 

 teenth century the East African indigo, I. arreda, 

 found its way from Zululand, through Natal, to Java ; 

 by the time that the competition of synthetic indigo 

 had begun to be serious, this African plant was 

 practically the only indigo cultivated in Java. 



Displacements of economic species depend on 

 economic factors. In the case of indigo, the explana- 

 tion has been either that the newly adopted species 

 was found to yield more leaf from a given cultivated 

 area or more dye from a given weight of harvested 

 leaf; in the case of East African indigo, it would 

 appear that Java experience has found these two 

 advantages combined in the same species. It was 

 not until 1898, as Mr. and Mrs. Howard explain in 

 their First Report, that it was realised in Bihar, 

 where the competition of S3mthetic indigo had at last 

 aroused concern, that in Java not merely one, but 

 two, displacements of the plant which was the basis 

 of the industry had taken place since India and 

 Malaya re-embarked upon it in the late eighteenth 

 century. Some Bihar planters then introduced the 

 African plant from Java ; a few seasons later direct 

 importation of seed of /. arreda from Africa took 

 place. 



The cultivation of East African indigo, which is in 

 India termed Java indigo, though it is not a native 

 of Java, and is in Java termed Natal indigo, though 

 it does not grow in Natal, gradually spread until 

 1909-10, and bade fair to displace Malayan indigo in 

 Bihar. An abnormal season, followed by another of 

 the same type, then led to a check. Indigo growers 

 became so alarmed at what they mistook for an out- 

 break of disease that by 19 13 the area under East 

 African indigo had fallen from 70,000 to 15,000 

 bighas. Had their memory enabled them to recall 

 the experience, duly recorded at the time, with regard 

 to the cultivation of /. arreda near Calcutta, under 

 equally abnormal conditions, ten years earlier, a 

 suspicion might have been aroused that what was 

 needed was the correction of some defect in the culti- 

 vation and the bestowal of some attention on the 

 seasonal peculiarities of the East African plant. The 

 investigation of the imaginary disease was placed in 

 the competent hands of Mr. Parnell at Sirsiah, who 

 in 19 13 was unable to report the discovery of any 

 pathogenic organism. Mr. Howard, who then had 



