GALLS 



Also known as nut-galls or gallnuts, noix de galle (Fr.); der Gallapfel (Ger.) 



The galls used in dyeing are nutlike in appeai-ance and are actually 

 infections on trees caused by certain insects. They are formed when female 

 gall-wasps (Cynips gallaetinctoriae) puncture the young buds on small 

 branches of certain species of oaks (especially Quercus lusitanica) and de- 

 posit their eggs within these punctures. This action stimulates surrounding 

 plant tissue to grow, eventually enveloping the gall larvae which con- 

 tinue to develop. If allowed to reach matui-ity, the insect punctures the 

 gall and escapes. 



The bluish or greenish-colored galls collected before the insects leave 

 them were richest in tannic acid. Other factors affecting tannic acid con- 

 tent of galls were the region in which they were grown and their har\'esting 

 season (August and September were best). The finest blue galls were 

 imported from Aleppo, Syria; slightly inferior qualities were those from 

 Smyrna, Turkey, and Tripoli, Libya. Galls of the same type were also 

 found in southern Europe on the Q,- sessiliflora and Q,- pubescens oak species 

 (Thorpe, 1912, vol. 2, p. 647). Although several 19th-century dyers voiced 

 the opinion that galls could be cultixated on American oak species, no 

 commercial amounts were ever produced here. Galls were purchased 

 either in powder or nut form; however, since there was always great 

 danger of adulteration when one purchased dye materials already ground, 

 whole galls were preferred. 



Galls d\ed only grays, and in compound colors, grayed yellows such as 

 drabs. Their most important use was in mordanting, rather than dyeing, 

 and they were most valuable in mordanting cottons that would later be 

 dyed dark neutrals or black tones. With few exceptions most natural 

 dyestuffs would not produce fast, deep colors on cottons without preparatory 

 treatment by tannin-rich substances such as galls. Since tannin is the 

 principal component of galls, making up 25 to 70 percent of the chemical 

 composition of the nuts, it is obvious that galls held an important place 

 among dyers' supplies. 



O'Neill reminded dyers of still another property of galls — an ability to 

 weight silks, giving them body without the aid of metallic salts: 



In the better class of blacks upon silks, galls are still much used ; they give a very durable 

 but somewhat grayish shade of color, and possess a property, very much esteemed in 

 certain trades, of weighting, i.e., accumulating on the fibre in such quantity as to add 

 very materially to the weight of the silk (1869, p. 231). 



Generally black dyers combined galls with iron salts and logwood? 

 adding madder and any other coloring material that would attain the 

 tone of black the customer or fashion dictated. 



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