1863.] 633 



can now be considered secure from railway injury, he wishes to make 

 them public, in hopes that they may be useful, not only to practical 

 astronomy, but to some other departments of science. 



V. " Preliminary Notice of an Examination ofRubia munjista, the 

 East-Indian Madder, or Munjeet of Commerce." By JOHN 

 STENHOUSE, LL.D., F.R.S. Received June 18, 1863. 



It is rather remarkable that while few vegetable substances have 

 been so frequently and carefully examined by some of the most emi- 

 nent chemists than the root of the Rubia tinctorum, or ordinary 

 madder, the Rubia munjista, or munjeet, which is so extensive!) 

 cultivated in India and employed as a dye-stuff, has been, compara- 

 tively speaking, very much overlooked, never having been subjected, 

 apparently, to anything but a very cursory examination. Professor 

 Runge, at the close of his very elaborate memoir upon madder, pub- 

 lished in 1835, details a few experiments which he made upon the 

 tinctorial power of munjeet, the constituents of which he regarded 

 as very similar to those of ordinary madder. Professor Runge stated 

 that munjeet contains twice as much available colouring matter as 

 the best Avignon madder. This result was so unexpected that the 

 Prussian Society for the Encouragement of Manufactures, to whom 

 Professor Runge' s memoir was originally addressed, referred the 

 matter to three eminent German dyers, Messrs. Dannenberger, Bohm, 

 and Nobiling. These gentlemen reported, as the result of numerous 

 carefully conducted experiments, that, so far from munjeet being 

 richer in colouring matter than ordinary madder, it contained only 

 half the quantity. This conclusion has been abundantly confirmed 

 by the experience of my friend Mr. John Thorn, of Birkacre, near 

 Chorley, one of the most skilful of the Lancashire printers. From 

 some incidental notices of munjeet in Persoz and similar writers, and 

 a few experiments which I made some years ago, I was led to suspect 

 that the colouring matters in munjeet, though similar, are by no 

 means identical with those of ordinary madder, and that probably 

 the alizarine or purpurine of madder would be found to be replaced 

 by some corresponding colouring principle. This hypothesis I have 

 found to be essentially correct ; for the colouring matter of munjeet, 

 instead of consisting of a mixture of alizarine and purpurine, contains 



