TRANSACTIONS OF THE SECTIONS. 00 



mentions its cultivation in Galilee. In this country its culture has often been 

 attempted, and has been carried on for a short time, but noA'er with permanent 

 success. The madder now used in England is imported from France, Italy, Hol- 

 land, South Germany, Turkey, and India. In 18.57 the total amount imported 

 into this country was 4.34,056 cwt., having an estimated value of £1,284,989; 

 and the average annual amount imported during the last seventeen years is 

 310,042 cwt., while the amount imported last year (1872) was 283,274 cwt., 

 valued at £922,244. In 1861 it was estimated that in the South Lancashire dis- 

 trict alone 150 tons of madder were used weekly, exclusive of that required for 

 preparing garancine. I quote these figures as showing the magnitude of the 

 industry that we are dealing with. Another point of much interest is the amount 

 of land required for the cultivation of this plant : hi England it was found that an 

 acre yielded only from 10 to 20 cwt. of the dried roots ; but in South Germany and 

 in France the same amount of land yields about twice tliat quantity. The madder- 

 cultivator digs up the roots in autumn, dries them, in some cases peels them by 

 beating them with a flail, and exports them in the form of powder, whole root, or 

 after treatment with sulphuric acid, when it is known as Garancine. 



The quality of the root varies much ; that from the Levant, and Imown as Tur- 

 key-root, is most valued. According, however, to the colour to be produced is 

 the madder from one source or another prefen-ed. To obtain the colouring-matter 

 (which is but very slightly soluble in water) from these roots, they are mixed, after 

 being ground, with waterin the dye-vessel, and sometimes a little chalk is added. 

 The fabric to be dyed is introduce"d, and the whole slowly heated ; the colouring- 

 matter gradually passes from the root to the water, and from the water to the 

 mordanted fabric, giving to it a colour dependent of course on the natm-e of the 

 mordant. 



To trace the chemical history of this colouring-matter we have to go back to 

 the year 1790, when a chemist of the name of Watt precipitated the colouring- 

 matter of madder by alum from neutral, alkaline, and acid solutions ; he obtained 

 two diflerent colouring-matters, but could not isolate them, and many different 

 shades of colour. Charles Batholdi asserted that madder contained much magnesic 

 sulphate ; and Hausmann observed the good effect produced on madder by the 

 addition of calcic carbonate. In 1823 F. Kuhlmann made evidently a careful 

 analysis of the madder-root, and describes a red and a fawn colouring-matter. But 

 the first really important advance made in our knowledge of the chemical consti- 

 tution of this colouring-matter was by Colin and Robiquet in 1827 ; they obtained 

 what they believed to be, and what has since really proved to be, the true colour- 

 ing principle of madder, and obtained it in a state of tolerable purity. Their 

 piocess for preparing it was very simple : they took Alsace madder in powder, 

 digested it with water, obtained thus a gelatinous mass, which they treated with 

 boiling alcohol, then evaporated off A of the alcohol, and treated the residue 

 with a little sulphuric acid to diminish its solubility ; then, after washing it with 

 several litres of water, they got a yellowish substance remaining. Lastly, they 

 foimd that, on moderately heating this product in a glass tube, they obtained a 

 yellowish vapour formed of brilliant particles, which condensed, giving a distinct 

 zone of brilliant needles reflecting a colour similar to that from the native lead 

 chromate. They named this substance alizarin, from the Levant name for madder, 

 alizari, the name by which it is still known there. 



A few years later we find other chemists attaclring this same subject. In 1831 

 Gaultier de Claubry and J. Persoz published the account of a long research on the 

 subject. They describe two coloiu'ing-matters, a red and a rose one : the red one 

 was alizarin ; and the rose one was another body nearly allied to it, and now well 

 known as purpurin. Runge also made an elaborate examination of the madder- 

 root; he found no less than five different colouring-matters in it — madder-red, 

 madder-purple, madder-orange, madder-yellow, and madder-brown. The first 

 three he considers to be suited for dyeing-purposes, but not so the last two. Rimge's 

 madder-red is essentially impure alizarin, and his madder-purple impure purpu- 

 rin. He does not give any analysis of these substances. 



During the next ten years this subject seems to have attracted but little atten- 

 tion from chemists; but in 1846 Shiel prepared the madder- red and madder-purple 



