or ether, and the application of Zinc Ointment (0. H. Foerster, 1910; Rost, 1914). Prirose dermatiLis has also been studied by Simpson, 1917.
Hypericum. — Ray, 1914, stated that cattle feeding on a Tunisian species (H. crispum) develop dermatitis of non-pigmented portions of the skin, and inflammation of the mucous membranes exposed to light. The phenomena are due to a fluorescent substance. Rogers. 1914, claims analogous effects for the common St. John's wort, Hypericum perforatum. Similar symptoms are also said to be sometimes produced by buckwheat.
The action of fluoresccnt dyes on plants is discussed by Gicklhorn, 1914.
PHYSICAL COUNTERIRRITANTS
Irritation of the skin is easily produced by physical agencies, which are often
preferred to the chemical irritants. The effects and indications arc similar. They can
only be enumerated here: heat and cold, in the form of applications, baths, heated air,
or cautery. Friction, generally combined with massage. Electricity, radiotherapy and
phototherapy.
Antiquated are: Acupuncture (pushing needles through the skin to the underlying organs, said to be popular with the Chinese); scarification (small incisions with knife or needle); selons (a string carried through a fold of skin and left to suppurate).
Venesection, cupping and leeches also act by altering the distribution of the blood.
DRUGS EMPLOYED FOR THEIR LOCAL EFFECTS ON THE ALIMENTARY CANAL
STOMACHICS
Bitter, aromatic and "sharp" drugs have been used since ancient times as "tonics," and in functional dyspepsias. They were supposed to increase the appetite and improve digestion, and thus favor nutrition.
Classification. — Simple bitters generally contain some "bitter principle" — neutral substances, often crystalline, non-nitrogenous, sometimes glucosidal, and without pronounced systemic actions. In aromatic bitters these are mixed with volatile oils. The astringent bitters contain tannin. Condiments, which also contain aromatic oils or other sharp principles, form the transition to carminatives. These are employed to secure the expulsion of gas from the alimentary canal.
EflSciency in Health and Disease. — About a tenth of the medicines mentioned by Hippocrates belong to this class, and they have always played a prominent rflle in folk medicine.
Modern scientific investigations (Moorhead, 1915) have confirmed that the bitters may improve deficient appetite, and the flow and quality (acidity) of the gastric juice, in conditions of poor health (anemia); although they have no effect on normal individuals (Carlson and co-workers, 1914 and 1915).
Bastedo, 1930, states that hitters increase the appetite in achylia gastrica, although they have no effect on the secretion. He considers them especially valuable in convalescence after acute illness.
The aromatics and condiments probably act by mild direct irritation of the gastric mucosa, the beneficial effects being due to the hyperemia and motor stimulation.
Effect in Experimental Cachexia. — In dogs provided with a Pawlow gastric pouch. and rendered cachectic by repeated large hemorrhages, Moorhead, 1915, found that the administration of bitters improved the appetite and the gastric deficiency, although not quite to normal. Tbe animals consumed more food and the gastric juice became more abundant and more acid. The increase of appetite occurred whether the bitters were
