The fresh juice of the fruits was found by Köhler (1869) to contain 95 per cent. of water, 3 to 3·5 of organic and 1 to 1·6 of inorganic constituents. The same chemist observed that the percentage of elaterin gradually diminished as the season advanced, until in the month of September he was unable to obtain any of it whatever.
Walz (1859) found in the juice of the fruits and herb of Ecballium, as well as in that of Cucumis Prophetarum L., a second crystallizable bitter principle, Prophetin, and the amorphous substances Ecballin or Elateric Acid, Hydro-elaterin, and Elateride, all of which require further examination.[1128] Prophetin is a glucoside,—not so the other principles. The four together constitute, according to Walz, 8·7 per cent. of elaterium, which moreover contains about the same percentage of pectic matter.
Uses—Squirting cucumbers are only employed for making elaterium, which is a very powerful hydragogue cathartic.[1129] Elaterin is not employed in medicine, but seeing how much elaterium is liable to vary from climate or season, it might probably be introduced into use with advantage.
FRUCTUS COLOCYNTHIDIS.
Colocynth, Coloquintida, Bitter Apple; F. Coloquinte; G. Coloquinthe.
Botanical Origin—Citrullus Colocynthis Schrader (Cucumis Colocynthis L.)—The colocynth gourd is a slender scabrous plant with a perennial root, native of warm and dry regions in the Old World, over which it has an extensive area.
Commencing eastward, it occurs in abundance in the arid districts of the Punjab and Sind, in sandy places on the Coromandel coast, in Ceylon, Persia as far north as the Caspian, in Arabia (Aden), Syria, and in some of the Greek islands. It is found in immense quantities in Upper Egypt and Nubia, spreading itself over sand hillocks of the desert after each rainy season. It further extends throughout North Africa to Morocco and Senegambia, in the Cape de Verd Islands, and on maritime sands in the south-east of Spain and Portugal. Finally, it is said to have been collected in Japan.
History—Colocynth was familiar to the Greek and Roman, as well as to the Arabian physicians; it also occurs in Susruta (“Indravārunī”); and if we may judge by the mention of it in an Anglo-Saxon herbal of the 11th century,[1130] was not then unknown in Britain. The drug was collected in Spain at an early period, as is evident from an Arabic calendar of a.d. 961.[1131]
The plant has been long cultivated in Cyprus, and its fruit is mentioned in the 14th century as one of the more important products of the island.[1132] Tragus (1552) figured the plant, and stated that the fruit is imported from Alexandria.
Description—The colocynth plant bears a gourd of the size and shape of an orange, having a smooth, marbled-green surface. It is sometimes imported simply dried, in which case it is of a brown colour; but far more usually it is found in the market peeled with a knife and dried. It then forms light, pithy, nearly white balls, which consist of the dried internal pulp of the fruit with the seeds imbedded in it. This pulp is nearly inodorous, but has an intensely bitter taste, perceptible by reason of its dust when the drug is slightly handled. The balls are generally more or less broken; when dried too slowly they have a light brown colour.