Page:The New International Encyclopædia 1st ed. v. 12.djvu/373

LITHIC ACID DIATHESIS. 331 LITHIUM. color and is iiioif aL-itl, of liiglier specific {gravity, and less abundant than tlic urine of health. It deposits urates on cooling, and it may contain albumen or traces of sugar. The output of uric acid is low. There is a motley group of symptoms (one writer has enumerated thirty-nine) indicative of the litluemic state. Persons who have lived not wisely but too well, who have eaten and druik largely, and persons who lead sedentary lives. may manifest it. Cases are seen in members of gouty families, who may never themselves have sufl'ered from that disease. In such a family the daugliters often escape, while one son may have litluemic attacks of great severity, even though he ma_v lead a temperate life and try in every way to avoid the conditions favoring the disorder. Cuta- neous eruptions, such as eczema, are frequently associated with this diathesis; as are also dis- orders of the stomach and intestines, such as furred tongue, foul breath, and constipation. It may be accompanied by symjjtoms of a torpid liver. There may l)e a swelling of the parotid gland, simulating munijis. Disorders of the circulatory system are fre- quently associated. The blood tension is per- sistently high, the walls of the blood-vessels hecome stiff, and heart and kidney changes grad- ually develop. Then dropsy may supervene. It is not unlikely that the lithoemic state may hasten the development of aneurism or apo- plexy; for the nutritional disorder with which an excess of uric acid is associated induces in time increased tension in the blood-vessels, hardening of the arteries, chi'onic kidney dis- ease, and changes in the muscular tissue of the heart. Among nervous manifestations headache is fre- quent. Neuralgias, particularly sciatica, are not uncommon. There may be hot or itching feet at night. This symptom is as old as Plutarch, who ob.served it and called it 'the lisping of the gout.' Cramps in the legs and hot and itching eyeballs may be signs. Chronic bronchitis is frequent in such cases, as are also certain affections of the eye. such as iritis, retinitis, and glaucoma. The treatment is hygienic, dietetic, and medici- nal. The lith:emic should live temperately, ab- stain from alcohol, and eat moderatel.v. He should live in the open air, exercise vigorously, and keep regular hours. The skin should be kept active by cold baths with friction for the robust, and by warm evening baths for the debilitated. The dress should be warm, e.xtremes of temperatures should lie avoided, and care should be taken not to have the skin suddenly chilled. The appetite should be kept within reasonable bounds, meals should be at stated intervals, and food should be well chewed and eaten slowly. In the matter of food, quantity is a factor of more importance than quality. Each individual case should re- ceive separate consideration from the physician. Nowhere, perha|)s. is it more necessary than in lithiemia to consider the man as well as the ail- ment, and Vtfry often more the man than the ail- ment. This is especially so when we consider the possible sequehp of this state. Among medicines, wine of colchieuni, citrate of potash or of lithimn, sodium salicylate, iodide of potash, guaiacum, quinine, piperazin, and the bitter tonics are cm- ployed. For external application, warm fomen- tations, ichthyol, and steaming are appropriate. Vol. XII.— 22. Whenever the bloo<l becomes increasingly alka- line, some of the accumulated acid is washed out of the spleen and the joints, and, before it is elimi- nated from the system, atta(^ks the nerve-centres and the blood-vessels. The result is headache and de|)ression of spirits. Acids relieve these syiiiptoms, bnt cause further accumulation in the joints and spleen, with later serious results. (8ec tioiT: RiiEUM.TlSM.) Consult: Haig, Uric Acid (in (I Factor in the Causation of Disease (Phila- delphia, 1000) : Miles, Muscle. Brain and Diet (London, 1000) ; Brunton, Disorders of Assimila- tion. Diiirstioii. etc. (London, lilOn. LITHIUM (Neo-Lat., from Gk. XWot, stone). A metallic chemical clement, whose oxide was discovered in 1817 by .rfvedson. The metal itself was first obtained liy Hrande in 1822, and a quarter of a century later IJunsen and .lat- thiessen invented the process now used in mak- ing it (see below). Lithium is distributed in na- ture widely, but in very small qiantities, the only minerals containing considerable amounts of it Ix'ing the rare minerals spodumcne, petante, and lepiclolite. It is also found in certain min- eral waters, and in the leaves of ccrt.-tin plants. Finally, it occurs in meteorites, and its presence has been detected in the suu. Lithium com- pounds being used in medicine, the .sources of the element, especially lepidolite, are exploited on a considerable commercial scale. The mineral is first fused, so as to render it capable of being decomposed by strong hydrochloric acid; the latter is then caused to act on the mineral for several hours, nitric aeid is added to the result- ing .solution, then the solution is diluted and neutralized with sodium carbonate, which pre- cipitates out the iron, alumimim, magnesium, etc. On filtering, the liquid is evaporated to a small bulk and mixed with a strong solution of sodium carbonate, which now causes the precipitation of litliium carbonate. This carbonate ma_v then be transformed into other lithium compounds, among which the chloride may be used to obtain metallic lithium, by means of a strong voltaic current passed through the fused salt. The element lithium (synd)ol Li; atomic weight. 7.0:3) is the lightest metal known, its spe- cific gravity being about 0.50. It is white, it can be pressed into wire, and it can be welded at ordinary temperatures. If exposed to the air, it soon becomes covered with a yellowish white film of oxide. Like sodium and potassium, with which it is classed as one of the "alkali metals.' it decomposes water with great readiness. It is, on the other hand, less volatile than sodium or potassium, and does not distil at a red heat. Its melting-point is ISO' C. (.fO-i" F.). LiTiiiiM CoMi'OfNDS. .mong these deserve mention the oxide, the carbonate, the citrate, and the salicylate. The oxide. Li.O, may be prepared by heating the carbonate with charcoal; with water it forms the hydroxide, LiOII, which may. by crystallization from acpieous alcohol, lie obtained as LiOH -f H.O; the hydroxide may also be prepared by the action of lime on lithium car- bonate. The carbonate of lithium. Li~CO,. is a light, white powder sparingly soluble in water, hut insoluble in alenhol. The citrate of lithium, Li-C„11...0.. is a white powder readily soluble in water; it may be prepared by the action of citric acid on lithilim carbonate; 'efrervescent lithium citrate' may be prepared by mixing sugar with citric acid, drving the mixture and adding to" it