22 
By means of its readily-soluble calcium salt, a liquid acid of the 
boiling point 114 to 115° (4 mm) could be separated from the crude 
acids, of which the silver salt on analysis gave the following values: 
0,2802 g yielded 0,4206 g COg, 0,1486 g H2 O and 0,1152 g Ag; 
0;2544 g „ 0,3810 g CO2, 0,1342 g H2 O „ 0,1045 g Ag. 
0,2571 g after heating yielded 0,1052 g Ag, 
0,0911 g Ag, 
0,0980 g Ag. 
Calculated for 
V C, O, Ag: 
— 41,06 per cent 
40,86 41,06 „ 
acid Qj H^Q , presumably 
0,2221 g 
0.2399 g 
C 
H 
40,94 
5,89 
Ag 41,11 
II 
40,85 
5,86 
41,08 
Found: 
III 
IV 
40,92 41,10 
question of an 
It is, therefore, a 
belonging to the oleic acid series. 
In view of the great importance of the camphor production, it 
would probably not be lacking in interest to obtain some light on 
the formation of this body in the camphor tree. A work which 
refers to this matter, and which deals with the history of the develop- 
ment of the organs (in the first place the wood, and secondly the 
leaves) which come especially under consideration in the production of 
camphor, has been supplied by A. Tschirch and Homi Shirasawa^). 
The researches in this case were made partly with the living, and 
partly with dead material. According to this examination, camphor 
is the product of conversion of an essential oil which is formed in 
special oil cells. These oil cells are present in every part of the 
tree; they are formed already in the early stages during the develop- 
ment of the organs, but at first do not contain any essential oil. 
The latter is, on the contrary, only formed gradually, and then has 
a yellow colour which it retains for a considerable time. Subsequently, 
and that in many cases only years after the formation of the secretion, 
the yellow oil becomes colourless; it is then much more volatile than 
in the first stage. It has now also acquired the property of crystallising; 
consequently, it often happens that irregular bright masses of crystals 
which consist of camphor are separated out in the cells. The very 
volatile, colourless oil, formed in the oil cells, now clearly penetrates 
the entire body of the wood, and its vapour therefore enters also into 
the cavities and fissures. Here the conditions are particularly favourable 
for crystallisation, and it follows that an abundant separation of crystals 
^) ArcMv d. Pharm. 240 (1902), 257. 
