This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Carthamus Pharm. Paris. Cnicus sativus five carthamus officinarum C. B. Carthamus tinctorius Linn. Safflower: a plant with oval pointed leaves, somewhat prickly about the edges, joined close to the stalk, which is round, firm and branched: on the tops grow large scaly heads, with saffron-coloured fistular flowers standing out from them: these are followed by smooth white seeds, of an oblong roundish shape, yet with four sensible corners, remarkably heavy so as to sink in water. It is an annual plant, a native of Egypt, and cultivated in large quantity in some parts of Germany on account of the uses of its flowers in dying. It is some-times raised among ourselves; but the seeds, which are the part that has been chiefly made use of in medicine, seldom come to perfection in this climate.
(a) Vide Profp. Alpin. Dialog. de balsamo.
The seeds of carthamus, freed from the shells, have an unctuous sweetish taste, which on chewing them for a little time becomes acrid and disagreeable: they form an emulsion on trituration with water, and give out to spirit a little nauseous acrid matter. They have been celebrated as a gentle cathartic, in doses of a dram or two in substance and six or eight drams in emulsion: but as they operate very slowly, and are apt, especially when given in substance, to occasion nauseae, flatulencies, and distensions of the stomach; their use has long been laid aside, and the colleges both of London and Edinburgh have now discarded them from their catalogues of officinals.
The flowers have been sometimes employed as a colouring drug for alimentary and medicinal substances; and when well cured, are not easily distinguishable by the eye from saffron, though they have nothing of its smell or taste. They give a deep saffron tincture to rectified spirit, and a paler yellow to water. After the yellow matter has been extracted by water, the flower appears red, and communicates a deep red colour to spirit of wine or to alkaline lye.