24 ‘ REPORT—1846. 
3138 | 2/38 
|= \F | 2 | 23 
Name and Date. | & [ss Name and Date. ste (es 
$) 5 |82 213 |\83 
“|2 les z |e 
1843. 1844, 
129. Cheiranthus, sp.......... 80 | 388 | 7 ||141. Augusta Beans ......... 5| 5 
130. Dianthus chinensis...... 150 | 62 | 8 |142. Cobbett’s Wheat ......) 27 | 12 
131. Diplotaxis tenuifolia ....300 | 4 | 19 1845. 
132. Augusta Beans ......... 30 | 30 | 9 ||143. Augusta Beans ......... 30 | 27 
133. Linum usitatissimum ...|200 | 56 | 7 |\144. Cobbett’s Wheat ...... 15 | 14 
134. Melilotus leucantha ...|100 | 60 | 7 About 23 years old. 
135. Onopordon tauricum...|150 | 22 | 10 |145. Cashew Nut ........+ oa: Aa ealD 
136. — acanthium............ 100 | 40 | 10 |\146. Brazil Nut ............... 1 
137. Trifolium giganticum.../100 | 38 | 4 147. Longan .s......seeseeeees 2| 0 
135. —, Alsike Clover ...... 100 | 0 148. Quercus, Sp. secceecesers 4| 0 
139. Vicia lutea ..............- 100 | 27 | 31 |/149. — Aigilops..........++... 3| 0 
140. Fullard’s German Mar- 150. Ricinus .......-scccesress 5| 0 
FOWAEAG toknannspchee === 150 |100 | 7 |151. Rhizobolus Pekza ...... 1| 0 
W. H. Baxter, Curator. 
On the Colouring Matters of Madder. By Dr. Scuuncx. 
Tue organic colouring matters present such a wide tield for inquiry, that it 
would require the labour of years to enable one person fully to elucidate their 
properties, or even to bring this department of organic chemistry into a state 
of development proportionate to the present condition of the science. The 
substances included under the name of colouring matters by no means agree 
in their chemical characteristics; they merely coincide in being possessed of 
certain vivid colours, or in giving rise to coloured compounds. Strictly con- 
sidered, some of them ought to be classed among the resins and others among 
the extractive matters; and on the other hand, if we attempt a definition of 
the class according to their chemical characteristics, we shall find it impossible 
to exclude a large number of bodies, which, like tannin and catechin, are 
capable of giving rise under peculiar circumstances to brown substances, 
which in nowise differ in their general properties from the bright red colour- 
ing matters of archil, logwood, &c. Some colouring matters are presented 
to us ready formed in the different parts of plants and animals; others are 
produced artificially from colourless substances, which undergo very complex 
changes during the process ; others arise spontaneously during the first stages 
of oxidation or putrefaction following the extinction of organic life. In the 
investigation of substances thus widely differing in properties and formation, 
it would be vain to expect at present anything approaching to general results 
in regard to the class as a whole. I must therefore content myself on this 
occasion with giving a short account of the results of some experiments 
which I have made on one branch of the subject, at the same time apologising 
for their present vague and undefined nature. 
I have directed my attention in the first instance to madder, partly because 
the colouring matters contained in it are almost unknown, or rather worse 
than unknown, viz. known in such a manner as merely to mislead those who 
wish to inform themselves by the accounts given of them, and partly because 
madder is an article of such an immense importance in the art of dyeing that 
every discovery in relation to it acquires immediately a practical bearing. 
It will be unnecessary for me to allude to the former numerous investiga- 
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