202 - On the Poison Tree of Java. (Marca, 
The general result of my observations has excited in my mind a 
hope, that the means I have used will be applied upon a more 
extended scale to aid the arts and manufactures of this country. By 
increasing the capacity of the reservoir, and the condensing power 
of the apparatus, the diameter of the jet may be also enlarged; 
and the consequence will be, that a power of fusion, the most ex- 
traordinary, as a work of art, which the world ever witnessed, may 
be emplvyed, with the utmost economy both of space and expen- 
diture, and with the most certain safety. As far as mineral sub- 
stances are concerned, the character of infusilility is for ever anni- 
hilated. Every mineral substance, not even excepting plumbago, 
has been fused. There remains, therefore; only one substance, 
namely, charcoal, to maintain this character; and if I have leisure 
for a subsequent dissertation, 1 trust I shall be able to show that 
charcoal itself exhibits some characteristics of a fusible body. I 
must postpone my remarks upon this subject for a season. ‘The 
duties incumbent upon my public lectures in the University will 
preclude the possibility of my making any further experiments 
before the beginning of the next summer; when, if any thing 
should occur, that may be deemed worthy of insertion in your 
Annals, it shall be duly communicated. 
1 have the honour to be, &c. 
Cambridge, Jan. 23, 1817. Epwarp DanigL CuarRKE. 
a 
ARTICLE VY. 
in Essay on the Oopas, or Poison Tree of Java, addressed to the 
Honourable Thomas Stamford Raffles, Lieutenant Governor. 
By Thomas Horsfield, M.D. (Communicated to the Society 
by the President.) * 
’ T HAVE proposed to myself in the following Essay to offer you a 
short account of the oopas of Java. I feel some satisfaction in 
being able, at a time when every subject relating to this island has 
acquired a degree of interest, to furnish you with a faithful de- 
scription of the tree, made by myself on the spot where it grows, 
and to relate its effects on the animal system by experiments per- 
sonally instituted and superintended ; and I flatter myself that the 
practical information detailed in tne following sheets will refute 
the falsehoods that have been published concerning this subjeet, at 
the same time that it will remove the uncertainty in which it has 
been enveloped. 
The literary and scientific world has in few instances been more 
grossly and impudently imposed upon than by theaccount of the pohon 
oopas, published in Holland about the year 1780. The history and 
* From the Batavian Transactions, vol, vii. Published at Batavia in 1814. 
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