— 13 — 
This discovery of the aldehyde may probably lead to a simple 
differential diagnosis between shu-yu and camphor oil. For, according 
to Gildemeister, camphor oil only contains acetic aldehyde, — a fact 
which I myself proved in several samples of camphor oil. Although 
I do not know whether the formaldehyde in shu-yu is derived from 
the original material, or is formed by the method of production, its 
content in the oil is very considerable, and its detection very easy. 
Theoretically it is certainly possible that formaldehyde may occur as 
a product of decomposition together with the methyl alcohol, when the 
wood is dried, but yet we have hitherto never found it in pyroligneous 
acid which has repeatedly been examined by us. If it were once and 
for all established that all kinds of camphor oil only contain acetic 
aldehyde, we should now have a convenient method of detecting 
adulteration with shu-yu. 
Now with regard to apopinol, the direct demonstration of its presence 
is not yet satisfactory, but by detecting citral I was able to assume its 
presence indirectly. It goes without saying that this apopinol is also 
valuable for the recognition of shu-yu. 
I suspect that there are still some unknown terpenes also present 
in shu-yu, but I do not believe that they are of sufficient importance 
to be submitted to examination as important constituents. 
In conclusion I beg to express my thanks to Prof. Shimoyama 
and Mr. Nagai for their guidance, and Messrs. Morita and H agin a 
for their assistance. 
Basil Oil. Ocimum viride Willd., a species closely allied to 
the well-known Ocimum basilicum^ which contains in the oil-glands of 
the leaves abundant quantities of aromatic essential oil, has in recent 
times been recommended as a protection against mosquitoes. Ac- 
cording to Captain Larymore, as communicated by Shipley in 
"Nature", four plants placed round the bed afford greater protection 
than a mosquito-net. This effect is, however, denied by J. P. Quint on ^). 
An infusion of the leaves, taken hot, is used in Sierra Leone as 
a diaphoretic in high fever, and has given good results. 
Bay Oil. The distillation of bay -leaves imported direct from 
the West Indies, is carried on by us on a large scale. A sample- 
consignment from Bermuda yielded an oil of a widely divergent 
character which cannot replace in practice the distillate from the West 
Indian material. 
This oil, obtained in a yield of 1,33%, showed the following con- 
stants: digo = 1,0301; = — 3°4'; nj)2o° = i,530i2; phenol- 
^) Annual Report on Government Gardens and Parks in Mysore for the year 
1902/03, II. This Report also contains a good picture of Ocimum viride Willd. 
and some parts of the plant. 
