Gautier (1877) also obtained the two latter products, but he is of the
opinion that they are due to a somewhat different reaction, the formula
of catechin, as derived from his analyses, being C₂₁H₁₈O₈. He also
asserts that the so-called catechin from Uncaria (see Gambier) is not
identical with the substance under notice, nor with that found in the
Mahogan wood, to which Gautier assigns the formula C₄₂H₃₄O₁₆.
Crystallized deposits of catechin are sometimes met with in fissures of
the trunk of Acacia Catechu, and used medicinally in India under the
name _Keersal_.[936]
Löwe (1873), by exhausting cutch with cold water and then agitating
the solution with ether, obtained upon the evaporation of the latter a
yellow crystalline substance which he ascertained to be _Quercetin_,
C₂₇H₁₈O₁₂. Its solubility in water is probably favoured by the presence
of catechin, water having but very little action upon pure quercetin.
The amount of quercetin in cutch is exceedingly small.
When either cutch or gambier is subjected to dry distillation it
yields, in common with many other substances, _Pyrocatechin_, C₆H₄(OH)₂.
=Commerce=—The importations of cutch into the United Kingdom from
British India (excluding the Straits Settlements and Ceylon) were as
under, almost the whole being from Bengal and Burma:—
1869 1870 1871 1872
2257 tons. 5252 tons. 4335 tons. 5240 tons.
The total value of the cutch imported in 1872 was estimated at £124,458.
=Uses=—Cutch under the name of _Catechu_, which name it shares with
gambier, is employed in medicine as an astringent.
=Analogous Products=—See our articles Semen Arecæ and Gambier.