3) West Indian Bulletin 9 (1908), 275; Report of Schimmel 7 Co. April 1909,25.

4) 1. Giglioli, La canfora italiana. Rome 1908 (300 pages); Report of Schimmel & Co. October 1908, 35.

5) ). K. Nock, Circuit, and Agricult. Journ. of the Roy. bot. Gardens Ceylon 4 (1907), No. 3, p. 13; Report of Schimmel & Co. October 1907, 25; April 1908, 23.

6) Arch, der Pharm. 240 (1902), 257.

The number of the oil cells depends on climatic conditions and locality. Thus the specimens of the camphor tree grown in the green-houses of the botanical garden at Bern contained decidedly less oil cells than those obtained from Java. Particularly striking was this difference in the petioles, for the leaf stalks of the camphor tree, as of all other Lauraceae, are the organs richest in oil cells.

In the older trees camphor occurs in crystalline condition in the crevices of the trunk. Principally, however, it occurs dissolved in a volatile oil that permeates all parts of the plant. This oil occurs most abundantly in the underground roots, less abundantly in the trunk, and still less so in the branches, twigs and leaves. Moreover, the camphor oil content varies with the height in the tree, diminishing upwards. The older the trees and the firmer their wood, the higher the camphor content.

The proportion of solid camphor and camphor oil appears to vary with the age of the tree, the season of the year and the temperature. Young trees yield upon distillation more camphor oil and less camphor. The same is true with higher temperature, the yield of oil in summer being greater than in winter. At summer temperature, moreover, more camphor is dissolved in the oil than in winter time.

The amount of oil contained in the several parts of the plant have been determined by Professor Moriya1) of the College of Agriculture of the Imperial University.

Twigs............ 2,21 p.c.

Branches....... . . 3,70 „

Upper part of the stem..... 3,84 „

Lower part of the stem..... 4,23 „

Upper part of the stump..... 5,49 „

Lower part of the stump..... 5,74 „

Root . . •.......... 4,46 „ 2)

1) J.W.Davidson, The Island of Formosa. London and New York 1903,425. 2) Schimmel & Co. determined the oil content of the root at 4 p.c. Report of Schimmel & Co. October 1892, 11.

Hence the average is 4,22 p.c. These data reveal the fact that the lower portions of the tree are richer in oil than the upper portions. In addition it was ascertained that in winter the tree yields more camphor, in summer more oil.

With regard to the yield from the leaves, omitted in the above tabulation, a large number of data have been recorded which vary between 0,23 and 3 p. c. However, they are not directly comparable since some of them refer to the amount of camphor that had been separated in a variety of ways, others to the amount of oil. Hence they are not recorded in detail.

Upon the distillation of dried leaves, Schimmel & Co.1) obtained a yield of 1,8 p.c. The oil consisted of a liquid permeated with camphor crystals. D. Hooper2) reports a yield of 1 p.c. from fresh leaves .from the Government gardens at Ootaka-mund, India. V. Lommel3) distilled comminuted fresh leaves and twigs on a larger scale and obtained 1,2 p.c. of an oil rich in camphor.

Later, the same author4) contributed an interesting communication on the distillation of dried camphor leaves. He reports first on the distillation of leaves that had been obtained from a small cinchona grove, shortly before the rainy season. They had been spread out to dry but were not dried completely. The yield of camphor was so small that the percentage was not even calculated. Indeed the experiment was regarded as a failure.

For a second experiment the dry leaves that had accumulated on the ground between the hedges of a plantation were used. Their distillation yielded 0,06 p. c. of a crude camphor and 0,19 p.c. of camphor oil. Hence long lying on the ground with alternation of rain and sunshine had caused them to lose almost all of their volatile substance.

Finally, a young plantation was trimmed moderately, the fresh leaves were dried on the cleaned ground under the shade of cultivated cinchona trees. After 14 days the leaves had dried to such an extent that they could be stripped from the twigs without difficulty. They were packed in sacks and shipped to the place of distillation. This experiment yielded favorable results. The yield amounted to 1,55 p. c. of crude camphor and 0,49 p.c. camphor oil. It might have been larger, but for the fact that the condensation water at one time during the distillation became hot, thus allowing an appreciable amount of camphor to be lost.

1) Report of Schimmel & Co. October 1892, 11.

2) Pharmaceutical Journ. 56 (1896), 21.

8) Der Pflanzer 6 (1910), 86; Report of Schimmel & Co. October 1910, 27.

*) Der Pflanzer 7 (1911), 441.

Inasmuch as past experience seems to indicate that the trees may be trimmed twice annually, an annual crop of 9354 kg. of dried leaves per hectare may be expected from a 5 year old plantation. This would correspond to about 145 kg. of camphor and about 46 kg. of camphor oil.

In Jamaica experiments have also been made in the distillation of camphor leaves. H. W. Emerson and E. R. Weidleinl) found that the production of oil from the leaves may be carried on to advantage. 56,940 kg. of green leaves yielded 1353,8 gr. = 2,35 p.c. of distillate (1,32 p.c. of camphor, 0,54 p.c. of camphor oil and 0,49 p. c. of water). From 67 kg. of dried leaves they obtained 1719,5 gr. = 2,54 p.c. of distillate consisting of 1,57 p.c. of camphor, 0,46 p.c. of camphor oil and 0,51 p.c. of water. The green twigs yielded 0,58 p.c. camphor and 0,26 p.c. of camphor oil; the dried twigs contained 0,54 p.c. of camphor and the wood yielded upon distillation 0,61 p.c. of camphor.

Fairly extensive experiments on the production of camphor in the Federated Malay States have been described by B. J. Eaton -) in which he principally used leaves.