CHEMICAL AND MICROSCOPICAL INVESTIGATIONS. 29 
sought to add the nitrogenous element to the mother-substance by means of heating a solution of it, 
together with chloride of ammonium, in a sealed tube, for twenty-four hours, at a temperature of 200° Fah- 
renheit, hut found it entirely unchanged. Other tentative processes have not as yet proved more successful. 
I regret being unable to follow the curious chemistry of the parenchymatous cells of the liber and of the 
cellular envelope, hut must refer to what I have before written* to show that the flow of the nourishing 
sap not only conveys to these the substances on which this chemical transformation is effected, hut that 
also these products can be removed by the same circulation when the need of other parts requires, and the 
whole then becomes changed into the outside corky layer. 
The hot and dry air arising from the valleys of the Patia, was believed by Karsten to have been the 
cause of the inferior production of alkaloid in the trees of C. lancifolia growing on the volcano of Pasto.y 
This might well be the case if the material was used up by the plant for its necessities thus created ; as, in 
other cases, the provision of starch is consumed by the plant in flowering. 
The alkaloids must he regarded as highly complex, and, so to speak, animalized products of the general 
respiration,^ being in this way fitted to act powerfully on the animal economy (the blood having an alkaline 
reaction) ; as conversely acid gases of simple constitution (sulphurous, nitrous, etc.) are deadly poison to 
vegetables whose juice has an acid reaction. 
In studying the effect of the processes of chemical action continually going forward in the cells, I am 
obliged to feel the insufficiency of our skill and the incompleteness of our present appliances for investigating 
the secrets of this wondrous laboratory of nature. 
The determination of the constituent elements of organized structure by what we call analysis, must 
pass for what it is worth and no more. TV hen. we have dried all the molecules of water out of an egg, 
and then subject the remainder to analysis, we examine simply a spoiled product, differing so widely from 
the original that it can by no means he brought again into its primitive state, and all the remarkable 
capacities connected with its primitive organization are at an end. It is not different when we examine 
the vegetable cell ; with the utmost care and delicacy of research, the most important points still remain 
unexplained. The microscope reveals to sight much which chemical analysis cannot follow. 
Latest Remittance from the East Indies. 
In the month of August of the present year, 1868, I received the eighth remittance of specimens from 
Ootacamund, and have sent a Tteport thereon to the Indian Government, which the reader will find reprinted 
in the Appendix. 
I gather several points of instruction from the examination of these specimens : 
1. The permanence of the characteristics of species, § as far as ascertained by the present investigation. 
After all the changes and the varied treatment of the Cinchona succirubra, it appears to remain exactly the 
same in all material points as in South America. 
2. It appears that the renewed hark must derive its peculiarities from the nourishing sap, and not from 
the leaves, since the one-year-old renewed bark partakes of the five-years-old characteristics of the plant on 
which it grows. 
8. The implication of the resinous principle with the alkaloids increases with age in the C. succirubra , 
and thus produces increased difficulty in their extraction. 
d. On this account the lied Bark Tree should not he relied upon as forming the chief element in any 
plantation. 
* ‘ Microscopical Observations/ pi. ii. fig. 12 b, p. 2. t ‘The Chinchona Species of New Granada/ p. 97. 
X Analogous to Kreatin and Neurin in the animal economy. § See also under D. in the Appendix. 
I 
