905, 11, p.
373), who found that the equilibrium followed the law of mass-action
(see also F. W. Kuster, _Zeit. anorg. Chem._, 1904, 42, p. 453, R.
Lucas, _Zeit. Elektrochem._, 1905, 11, p. 457). Other metals, such as
nickel, iron, &c., can also react as catalysts. The use of finely
divided nickel (obtained by reducing the oxide in a current of pure
hydrogen at a temperature of 350 deg.) has been carefully studied by P.
Sabatier and J.B. Senderens; a summary of their results is given in the
_Ann. Chim. Phys._, 1905 (viii.) 4, pp. 319-488. Of special interest is
the condensation of acetylene. If this gas mixed with hydrogen be passed
over the reduced nickel in the cold, the temperature may rise to as high
as 150 deg., the acetylene disappearing and becoming replaced by a
substance like petroleum. If the nickel be maintained at 200 deg., and
the gases circulated for twenty-eight hours, a product, condensible to a
yellow liquid having a beautiful fluorescence and boiling at 45 deg., is
obtained. This substance closely resembles ordinary Pennsylvanian
petroleum. If acetylene be passed alone over nickel heated to 200
deg.-300 deg., a mixture, boiling at 60 deg.-70 deg. and having a green
colour by diffused and a red by transmitted light, was obtained. This
substance closely resembles Caucasian petroleum. The decomposition of
carbon monoxide according to the reaction 2CO <=> C + CO2 is purely
catalytic in the presence of nickel and cobalt, and also in the presence
of iron, so long as the amount of carbon dioxide present does not exceed
a certain amount (R. Schenck and W. Heller, _Ber._, 1905, 38, pp. 2132,
2139). It is of interest that finely divided aluminium and magnesium
decompose methane, ethane, and ethylene into carbon and hydrogen in the
same way as nickel. Charcoal at 350 deg. also reacts catalytically; for
example, Senderens found that ethyl alcohol was decomposed by animal
charcoal into methane, ethylene, hydrogen, carbon monoxide and a little
carbon dioxide, and propyl alcohol gave propylene, ethane, carbon
monoxide and hydrogen, while G. Lemoine obtained from ethyl alcohol and
wood charcoal a mixture of acetaldehyde and hydrogen.

CATAMARAN (a Tamil word, from _catta_, to tie, and _maram_ wood), a
surf-boat or raft used by the natives of Madras and along the Coromandel
Coast in India. It is usually made of three tree trunks lashed together,
the centre trunk being the largest and longest, and having one end be