[5] PRESERVATION OF NETS AND SAILS. 299 



with which the nets are saturated from the herrings, and which rots 

 them rapidly unless they are continually cleaned. 



On inquiry at one of the largest manufacturers of nets in Boston, I 

 found, as was naturally to be expected, that the net makers use catechu 

 in a very different way from the fishermen; that is to say, they fix it 

 methodically with bichromate of potash as would be done at a dye-house 

 in the case of any other cotton or linen goods. By the manufacturers, the 

 nets are steeped in a hot aqueous solution of catechu, and then treated to 

 a bath of the bichromate, whereby the color is oxidized, darkened, and 

 " fastened " to the twine in the manner familiar to dyers. It is a pro- 

 cess that has to be managed with care lest the netting should be weak- 

 ened. Extract of hemlock bark, they told me, might be used instead of 

 catechu, but it would cost more. It is only the lighter nets, such as her- 

 ring nets, that are stained with catechu in Boston. The heavier nets are 

 tarred; and, according to my informant, his firm tar many more nets 

 than they tan. It did not appear that tar and catechu are used together 

 by the Boston dealers, as they are in some places. 



It is a fact well known to dyers that linen and cotton can be stained, 

 after a fashion, by the use of tanning materials even when no mordant 

 is present. Bancroft^ says : " There is a species of coloring matter 

 diffused in greater or lesser proportions through the barks and other 

 parts of almost all trees and shrubs, and which, without any basis or 

 mordant, permanently dyes or stains wool, silk, cotton, and linen, of that 

 particular kind of color which the French call fauve (fawn color), and 

 sometimes cmdeur de racine ou de noisette (root or hazel nut color). * * * 

 It is found most abundantly in the peelings, rinds, or husks of walnuts, 

 in the roots of walnut trees, in alder bark, etc.; and it seems to acquire 

 both body and permanency by attracting and combining with pure air." 

 Domestic processes of dyeing cotton, in this sense, by simply soaking in 

 tan liquor and ageing, are sometimes mentioned in the agricultural 

 uewspapers.2 But in spite of this familiar knowledge, it would still be 

 remarkable if so dark and so durable a color as is actually seen on the 

 sails in some regions had been imparted to them by merely soaking or 

 boiling the canvas in tan liquor. As bearing upon this point, I may cite 

 the following sufficiently explicit statement from a very old authority .^ 

 For the sake of enforcing the contrast between cotton and wool the 

 author premises that "vegetable filaments, and thread and cloth pre- 

 pared from them, differ remarkably from wool, hair, silk, and other 

 animal productions, * * * in their disposition to imbibe coloring 

 matters." And in illustration of the fiict, a special instance is noted, 

 as follows : 



" Fishing nets are usually boiled with oak bark or other like astrin- 

 gents, which render them more lasting. Those made of flax rece ive from 



1 "Philosophy of Permanent Colors," 1, 227, of the Philadelphia edition of 1814. 



^ See, for example, The Rural New Yorker, January 31, 1880, p. 80, and May 14, 1881, 

 p. 327; also. The Cultivator and Country Gentleman (•Albany), 1880, 45, 431. 



3 The chemical works of Casper Neumann, abridged by Wra. Lewis, London, 1759, 

 p. 429 note. 



