1963, Robert E. L. Masters, Patterns of Incest, p 269

There was a time when the “squish” manufactured by Mr. Frank Cooper at Oxford was not known very extensively outside the world of undergraduates. With the march of events though the fame of Cooper's Oxford marmalade has become world-wide, and the natural consequence is that a new factory has had to be built to cope with the increased business.

To this ſpecies of cockle, or ſhirl, belong moſt of thoſe ſubſtances called imperfect aſbeſti; and as the cockle perfectly resembles a flag from an iron furnace, both in regard to its metallic contents, and its glaſſy texture, it is no wonder that it is not ſoft enough to be taken for an aſbeſtus. It has however, only for the ſake of its ſtructure, been ranked among the aſbeſti; and it is ſurpriſing, that the fibrous gypſum, from Andrarum, in the province of Skone, has eſcaped being on the ſame account confounded with them. The ſtriated cockle, or ſhirl, compared to the aſbeſti, is of a ſhining and angular ſurface (though this ſometimes requires the aid of the magnifying-glaſs to be diſcovered) always ſomewhat tranſparent, and is pretty eaſily brought to a glaſs with the blow-pipe, without being conſumed, as the pure aſbeſti ſeem to be.

The significance of the molecular shape of the dyes in induction of the birefringence of polyanions is illustrated with topo-optical reactions of the Janus dyes. Janus red, yellow, green, black, and blue are cationic azo dyes[…]. All of these exhibit a moderate metachromatic effect with sulfated GAGs [glycosaminoglycans].