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sequent washing, however, destroyed, as was expected,the glossiness of the gummed silk, and reduced them bothto the fame appearance, so that the gum seemed to beof no manner of advantage : perhaps it is rather of dis-service than otherwise, by thickening the liquor, andmaking it more difficultly penetrate into the silk, in thesame manner as it renders, ink indisposed to sink intopaper. I likewise dyed some silk by the two processesdescribed in the foregoing section for woollen cloth,(page 410 and 411) and obtained by both of them a rustyblack upon white silk, and a very good black uponblue : so deep a blue as is allowed for the true black onfine woollen cloth, did not appear necessary for silk ; avery flight blue ground being here sufficient to make theblack both deep and durable.

It should seem therefore that silk is not, in any parti-cular manner, more averse than . wool to the receiving ofthe black dye; and that a good black may be dyed onsilk, with the same materials, in the fame method, andwith the same dispatch, as on wool and woollen cloth;of which a further confirmation will appear at. the end ofthe following section. It may be observed, that thoughlilk takes a sufficiently good black dye from the methodpractised for fine woojlfens, yet woollen does not take ablack from the process that has been appropriated to silk;for some pieces of white flannel having been put in alongwith the white silk in one of the trials of the Frenchprocess above described, the flannels became only brown,while the silk turned out black. Though a black maybe dyed on white silk without logwood or verdegris, thefirst of which is a necessary material for white woollen;yet an addition of both contributes not a little to improvethe colour on one as well as on the other.

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