Intelligence and Miscellaneous Articles, 235 
five coincide with the Boetian mark for the same numeral, and those 
of two others are very similar. The idea of local position, again, 
may have had an independent European origin ; the inconveniences 
of the abacus on paper would have suggested it by destroying the 
distinguishing boundaries, and inventing an arbitrary hieroglyphic 
for the representation of an empty square.” 
The author then proceeded to adduce evidence from some docu- 
ments recently discovered in support of these views. He showed 
from the Mentz MS. in the Arundel collection, in what manner the 
mode of operation with the abacus had been improved, so as to lead 
naturally to the present system. He then brought forward some 
passages from MSS. illustrative of the first employment of the zero ; 
and concluded by adducing an instance from a MS. of the translation 
of Euclid by Athelard, of the fourteenth century, belonging to the 
Arundel collection, in which the number 15 is written in these con- 
tractions, and without a division. 
XLIII. Intelligence and Miscellaneous Articles, 
PRECIPITATION OF IRON BY ZINC. 
M CAPITAINE states that when a plate of zinc is immersed in 
• a neutral solution of protochloride of iron, the zinc in a short 
time, especially if heated to ebullition, obeys the magnet and becomes 
brittle, and on continuing the immersion there remains only a friable 
fragment of pure iron. Nevertheless, as it may be suspected that 
some zinc may remain unacted upon, he has invented a very simple 
arrangement to avoid this inconvenience. It consists in immersing 
into the solution of iron a plate of copper perfectly cleaned and sol- 
dered at one end to a piece of zinc. It is very nearly the same ap- 
paratus as employed to obtain the lead tree, and it acts unquestion- 
ably in the same manner. The iron is deposited on the copper in 
a thin friable layer, having a metallic splendour, but without any ap- 
pearance of crystallization : this mode of operating has no other in- 
convenience than its slowness ; but in whatever manner it is con- 
ducted, there is always a disengagement of hydrogen, which con- 
tinues as long as the metallic precipitation . — Journal de CMmie Med. 
January 1840. 
ACTION OF CHLORINE ON THE CARBURETTED HYDROGEN OF 
ACETATES. 
M. Dumas has read a notice to the Academy, of which the follow- 
ing is an abstract. Acetic acid treated with chlorine yields chloro- 
acetic acid, and this under the influence of the alkalies is converted 
into carbonic acid and chloroforme. If there exist, as I have an- 
nounced, a similarity of type between acetic and chloroacetic acid, 
the first ought to give with the alkalies a carburetted hydrogen 
H^, corresponding to chloroforme H^ Cl®. The production of 
this carburet under the influence of the alkalies is not known; but of 
the carburet H® produced by the acetates corresponding to chlo- 
