June 1, 1903.] THE TROPICAL AaRlCULTUllLST. 841 
In the last few years the irapoitanco of finding ft 
satisfactory camphor snbstitiite has been iiicnasiugly 
reahsed, and the efforts of a large numbor of cheniista 
have been directed towards this end. The most obvious 
product to employ for this purpose is, of course, the 
product known fls artificial camphor, a terpens 
hydrochloiide. This substance appeared to worii 
entirely satisfactorily, but it was soon observed that 
celluloid articles manufactured with this subititute 
after a short time lo.t tlieir transparency and the 
delicacy of their colouring. Eventually, they became 
altogether brittle, and therefore useless. Although 
it was discovered that these cff xts were due to the 
presence in the artificial camphor of certain impuri- 
ties, the cost of effecting the necessary purification 
was found to be excessive. It appears that this diffi- 
culty has now been entirely overcome hy the discovery 
of an extremely cheap process for the refining of the 
artificial camphor, and it is stated that the pure 
product yielded by this process is greatly superior to 
real camphor in the mauufaclure of celluloid articles. 
In the meantime, however, a very large number of 
compounds have been patented, all of which are 
claimed to be satisfactory substitutes for part or the 
whole of the camphor used in the manufacture of 
celluloid. No doubt a considerable proportion of 
these alleged substitutes will never pass beyond the 
experimental stage in the manufacture of celluloid, 
but there is no doubt, on the other hand, that quite a 
number of them answer Iheii' puipose in a very satis- 
factory manr:er, and will pro^'e a most useful addition 
to the resources of the celluloid indn-itry.— India- Buhber 
Journal, April 13. 
PEESEEVING BOOKS IN THE TROPICS. 
The hooks sliouUl be litihtly painted ovkh- by 
means of a camel's-liair biush, both out.side and 
iaside the covers (and especially along the margins 
and backs where paste has beea used), with a 
ini.\;ture as follows: — 
1 oz. Corrosive sublimate, 
1 oz. (Jarbolic acid. 
2 pints methylated or white rum spirit. 
This solution (if caiefully applied) will etfeciuaUy 
preserve boolcs with either paper, cloth or leather 
covers from cockroaches and other insects. No 
harm will be done to the books, and after the 
mixture has dried tliey may bs handled with 
perfect safety. 
Every new book received should be at once 
treated in this manner. The result will be that 
they will keep in as j^ood order in the tropics 
as in temperate climates. 
Bookbinders in the tropics are recommended to 
use a paste poisoned hy adding half an ounce of 
copper sulphate (or blue slone) to every pound of 
paste. — A(/ricultural A^vws Jamaica. 
CITROKELLA OIL. 
(To the Ed'itor, '■Chemist and Druogisk.") 
Sir, — Our experiences as exporters ol citronella 
oil from Ceylon may possibly prove ot interest in 
view of the discussions and articles appearing in 
your journal on the a luUeratiou of this export. 
The prevention of excessive or, in fact, any 
adulleraiion rests mainly in the hands of the 
home importers, wdio wouKl obtain ;i very fair oil 
if they would pay a fair price, but who, availing 
tllem^elve^^ of the cutting competition which \^ as 
starteil a few years ag", so leduced the price of tlie 
oil that it has been an open secret for some time 
past that the distillers were unable to produce it at 
a proht to themselves unless they resorted to 
ndulteralicu, This policy of cut throat competition 
will exist as long as home buyers are content 
with Schimmel's test, which, according to our ex- 
perience, admits of an adulteration of about L5 
per cent, of petroleum. His Excellency Sir West 
Ridgeway, in his recent speech at the opening of 
the present sitting of the Legislative Council, re- 
ferred to the subject of the increasing adulteration 
of this Ceylon export and the consequent discredit 
which was coming over the trade. We immediately 
inquired of the Director of the Botanical Gardens 
as to tiie steps Government contemplated taking, 
and were informed that they proposed to plant up 
an acreage with the grass in order to demonstrate 
to the distillers that a better oil could be produced. 
We suggested that Government should rather cause 
every shipment exported to be analysed by the 
Government analyst ; buyers could then obtain 
an analysis of the shipment before ac- 
cepting it, and it would ultimately result 
in exporters being compelled to send such certi- 
ficates with each sliipment. Winter's oil, which, 
we notice, has formed the subject of one of the 
experiments mentioned, has always been exported 
by us as their agents. It is obtained from a grass 
imported years ago into the island by Mr Winter, 
and is nob identical with that cultiva^d by the 
natives ; in fact, it is only grown on his estates, 
and its distillation is supervised by a European 
manager, so that there is no question about its 
purity. 
Our experience having shown us that Schimmel's 
test was unreliable, we worked out and adoi)ted a 
test of our own, which gives, in our opinion, very 
satisfactory results, and for the disflosure of whicli 
we have had at least one offer. We have for many 
years in consequence been compelled to pay a 
higher rate for oil satisfying our test than we 
should have had to pay had we adopted the milder 
standard of purity, and, being adverse to shipping 
oil which would not pass our standard, we lost 
ground in the trade in proportion as the adultera- 
tion and the consequent difficulty in obtaining pure 
oil increased. In truth, the quality had fallen off 
to such an extent that during the past three years 
we have exported but a quarter of the quantity 
yearly than we had done during the previous six 
years. 
The test we employ is distinctly a practical one, 
and we have always obtained good results from 
it, though we would by no means claim that it i* 
better or surpasses a thorough quantitative and 
qualitative analysis at the hands of an expert 
analyst. Contrary to the opinion of Me.isr«. Parry 
and Bennett, and with all due deference to these 
gentlemen, we do not think that any resiu-spirit 
as a distinct article is the medium of adulteration. 
We have an intimate acquaintance with tiie 
distiicts where the oil is distilled, and are not 
aware of any other oil or resin-spirit being made 
which could be used as an adulterant ; but, in our 
opinion, the adulterant is the same as it has been 
for the last ten or fifteen years— namely, petro- 
leum or, as it is more commonly called here, 
kerosene. The only change that may possibly 
give rise to the suggestion arid presence of resin- 
spirit is that change in kerosene wliich lias taken 
place within the past few years, for the Russian 
bulk iieti oleum installations have almost alto- 
gether ousted the former American qualities, and, 
being carted from door to door as it is, a cheap, 
handy, and well-known adulterant is at hand to 
every native wishing to increase the quantity of 
his distillate. The differences between the two 
petroleums mentioned are very marked, and if 
