GALLS.

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other colouring matters to modify the shade. Cutch yields a variety of brownshades; also olive, wood-colour, and so-called bronze hues. The applicationsof catechu are, however, still limited, and it is doubtless capable of manymore valuable applications than it has yet received.

True Astringents.

We have now to turn our attention to some substances which are stridtlyastringents rather than dyes, and among these, in the first place, nut-galls.These are globular-shaped, dirty, brownish substances, having the size ofsmall marbles, the morbid excrescences produced by the pundtures of an insedtcalled Cynips G alla-tinctorice , belonging to the order Hymenoptera, upon theleaves and young twigs of several kinds of oak trees, and more especiallythose of Quercus infectoria, a small tree indigenous to India, Persia, Syria, theLevant, and some parts of Greece, and other portions of the South of Europe.The fully developed nut-gall contains a central cavity, wherein, on breaking itopen, will be found the larva of the insedt. The galls are generally gatheredand colledted before the larva has had time to become fully developed, andtherefore before it has consumed a portion of the internal layers of theenvelope by which it is enclosed, and escaped as a mature insedt. This fadtis mentioned here because it bears upon the qualities of nut-galls as distin-guished in commerce ; the non-perforated nuts, which are heavier than theperforated, are known by the name of blue, black, or true nuts ; the other kindare known as white or false nuts. The former are deemed preferable to thelatter, and command a higher price, but in the English market both kinds arefrequently found mixed together in the same parcel: the size and shape of thenut-galls vary, the latter being spheroidal or ovoid, and the former rangingfrom that of a pea to a diameter of from i to 2 centimetres. The exteriorsurface is more or less smooth, and with slight conical excrescences of varioussize. The chief commercial varieties are—

Aleppo Galls, or Turkey Galls. —Imported from Aleppo and Smyrna, whitherthey are brought from the interior of the country. This variety issubdivided into—Heavy black galls, of a blackish-grey colour withwhitish excrescences; greenish or bluish galls, with white excres-cences ; whitish-yellow wrinkled and pierced (false galls).

Morea Galls. —Of the size of hazel nuts, brown, irregular-shaped, and oftenquite hollow.

Smyrna Galls. —Greenish-black, greyish-black, and whitish-yellow; are aless esteemed quality than the Aleppo galls.

So-called Marmorine Galls. —Small, round, iron-grey coloured nuts, havinga smooth surface.

Istria Galls. —Very small, light, pale yellow-coloured.

French Galls. —Very small and light, smooth-surfaced, pale yellow-coloured.

Piedmontese Galls, known as 11 knoppern,” are irregular-shaped excres-cences developed upon the glands (acorns) of the Quercus pedunculate,the consequence of the pundture of an insedt, the Cynips Quercus-calycis, also belonging to the order Hymenoptera. This kind of nut-gall is gathered in Hungary, Dalmatia, Roumania, Styria, Piedmont,and other countries.

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