INDIAN TOBACCO. 



INDIGO. 



substances (such as copal), in combination 

 with very strong alcohol." 



The discovery of the chemical solvent which 

 forms the subject of the patent above described, 

 has excited considerable interest in the philo- 

 sophic world, not only from its probable use- 

 fulness as a new article of commerce, but also 

 from two very extraordinary characteristics 

 which it is found to possess, viz., that, in a 

 liquid state, it has less specific gravity than 

 any other liquid known to chemists, being con- 

 siderably lighter than sulphuric ether, and, in 

 a state of vapour, is heavier than the most 

 ponderous of the gases. 



Its elementary constituents are, 

 Carbon - - 6-812 - - 8 proportions. 

 Hydrogen - - I'OOO - - 7 ditto. 



This new material (when mixed with alco- 

 hol) is a solvent of all the resins, and particu- 

 larly of copal, which it dissolves, without arti- 

 ficial heat, at the ordinary temperature of the 

 atmosphere ; a property possessed by no other 

 solvent known; and hence it is peculiarly use- 

 ful for making varnishes in general. It also 

 mixes readily with oils, and will be found to 

 be a valuable and cheap menstruum for lique- 

 fying oil-paints ; and, without in the slightest 

 degree affecting the most delicate colours, will, 

 from its ready evaporation, cause the paint to 

 dry almost instantly. 



Cocoa-nut oil, at the common temperature 

 of the atmosphere, always assumes a concrete 

 form ; but a portion of this caoutchoucine 

 mixed with it will cause the oil to become fluid, 

 and to retain sufficient fluidity to burn in a 

 common lamp with extraordinary brilliancy. 



Caoutchoucine is extremely volatile ; and 

 yet its vapour is so exceedingly heavy that it 

 may be poured, without the liquor, from one 

 vessel into another, like water. (Ure's Diet.) 



INDIAN TOBACCO. See ETE-BHIGHT. 



INDIAN TURNIP (Arumtriphy Hum), Wake- 

 robin, &c. An American plant, distinguished 

 by its head of beautiful red berries growing 

 upon a single stem, and its perennial bulbous 

 root, resembling a small rough turnip, possess- 

 ing such an extremely acrid juice as, when 

 bitten or chewed, causes violent inflammation 

 in the mouth and salivary glands, inducing 

 copious salivation. This acrid quality of the 

 root is, however, dissipated by boiling or dry- 

 ing. The dried root, grated and boiled in milk, 

 is a popular remedy for coughs and pulmonary 

 consumption. 



The English wake-robin, or cuckoo-pint, is the 

 Arum Hiacitlatum, which in many of its sensible 

 qualities resembles the American Indian turnip. 



INDIGENOUS PLANTS. Such plants as 

 are natives of or are common to a country. 



INDIGO (Indigofera, from indigo, a blue dye- 

 stuff, a corruption of Indicum, India, and fero, 

 to bear; most of the species produce the well- 

 known dye called indigo, the finest of all vege- 

 table blues). This is an extensive genus of 

 rather elegant plants, the shrubby kinds of 

 which are well worthy of cultivation. The 

 stove and green-house shrubby kinds thrive 

 best in a mixture of sandy loam and peat, and 

 may be increased without difficulty by cuttings 

 of the young wood, planted in sand, under a 

 glass, in heat. The annual and biennial kinds 

 660 



1 must be raised from seeds sown in a hotbed in 

 I spring; and when the plants have grown a 

 sufficient height, they may be planted singly 

 into pots, and treated as other tender annuals 

 ! and biennials. The genus belongs to the natu- 

 j ral order Ltguminosa : hence the flowers resem- 

 ' ble the pea tribe. The vexillum is round, 

 emarginate ; the keel furnished with a subulate 

 spur on both sides; stamens diadelphous ; style 

 filiform ; legume continuous, one or more seed- 

 ed, two-valved. The Indigofera casrulea yields 

 the finest indigo ; the 7. argentia, an inferior 

 kind, which comes from Egypt ; the I. tinctoria, 

 besides yielding indigo, is also medicinally 

 employed ; and the powdered leaf of /. anil is 

 used in some diseases of the liver. (Paxton.} 

 Indigo, when cultivated, thrives best in a 

 free, rich soil, and a warm situation, frequently 

 refreshed with moisture. The usual course 

 pursued for its culture is as follows : 



Having first chosen a proper piece of ground, 

 and cleared it, hoe it into little trenches, not 

 above two inches or two inches and a half in 

 depth, nor more than fourteen or fifteen inches 

 asunder. In the bottom of these, at any season 

 of the year, strew the seeds pretty thick, and 

 immediately cover them. As the plants shoot, 

 they should be frequently weeded, and kept 

 constantly clean, until they spread sufficiently 

 to cover the ground. Those who cultivate 

 great quantities, only strew the seeds pretty 

 thick in little shallow pits, hoed up irregularly, 

 but generally within four, five, or six inches of 

 one another, and covered as before. Plants 

 raised in this manner are observed to answer 

 as well as the others, or rather better; but they 

 require more care in the weeding. They grow 

 to full perfection in two or three months, and 

 are observed to answer best when cut in full 

 blossom. The plants are cut with reaping- 

 hooks, a few inches above the root, tied in 

 loads, carried to the works, and laid by strata 

 in the steeper. Seventeen negroes are sufficient 

 to manage twenty acres of indigo; and one 

 acre of rich land, well planted, will, with good 

 seasons and proper management, yield five 

 hundred pounds of indigo in twelve months-, 

 for the plant ratoons (stools, stoles, or tillers, 

 i. e. it sends out stolones, or new growths), and 

 gives four or five crops a year, but must be re- 

 planted afterwards. (Browne.) 



The process by which the blue colouring 

 matter is extracted from the plant in Mexico, 

 the East Indies, &c., is as follows: 



The leaves are gathered at maturity, and im- 

 mersed in vessels filled with water till fermenta- 

 tion takes place. The water then becomes 

 opaque and green, exhaling an odour like that 

 of volatile alkali, and evolving bubbles of car- 

 bonic acid gas. When the fermentation has 

 been continued long enough, the liquid is de- 

 canted and put into other vessels, where it is 

 agitated till blue flakes begin to appear. Water 

 is now poured in, and flakes are precipitated 

 in the form of a blue powdery sediment, which 

 is obtained by decantation, and which, after 

 being made up into small lumps and dried in 

 the shade, is the indigo of the shops. It is in- 

 soluble in water, though slightly soluble in al- 

 cohol ; but its true solvent is sulphuric acid, 

 I with which it forms a fine blue dye, known by 



