POLYTECHXIC ASSOCIATION PROCEEDINGS. 899 



eight thick. The sparks were produced with detonations. A 

 single Bunsen element of small size was sufficient to produce these 

 phenomena. When two recipients are charged with mercury and 

 water, and fragments of iodine are added, no effect is perceived; 

 but if a small piece of zinc is allowed to fall into the mercury, the 

 fragments of iodine are instantly set in motion and are rapidly 

 dissolv^ed- This solution,, poured off clear,, serves for many uses. 

 M. Eondel has employed it concentrated, for the supplying of a 

 pile mounted in a closed fla;sk, also for the preparation of a fine red 

 iodide of mercury. 



THE PHEXIC ACID KEMEDT. 



Phenic acid, {earlal) which has produced of late some remark- 

 able results in hospitals, has also been employed with success on 

 the farm. Dr. Calvert, in a recent lecture said that carbolic (phenic) 

 acid is now used in England for the cure of certain diseases common 

 to sheep — scab, for example. The method of treatment customary 

 in similar cases was very imperfect as well as dangerous, while 

 with carbolic acid this malady is cured, and without danger ;to the 

 animal, by dripping it for a minute, often only for some seconds, in 

 water containing a small quantity of carbolic acid. For this 

 purpose pure acid would be too expensive and is not used, nor is 

 concentrated acid, which ignorant men who have the care of sheep 

 would not know how to use, but by the help of soap an emulsion 

 of carbolic acid and cresj'lic acids is made. After having shorn the . 

 sheep it is dipped in this mixture; a single emersion in a bath con- 

 taining one-sixtieth of it is sufficient to effect a cure. Phenic acid 

 is also an efficacious remedy for foot-rot. For this, a mixture is 

 made of the acid and an adherent and greasy substance, capable of 

 forming a plaster, which is made to adhere to the animal's foot for 

 two or three days, preventing the contact of the air, allowing 

 thereby time for the application to have its effect. But if the flock ' 

 be numerous, it would take a long time to dress the feet of each 

 animal one after another, so to make it more easy, a shallow tray 

 is made of stone, a sort of trough; this is filled with the medicated . 

 mixture, and the sheep made to. pass through it; their feet being 

 thus impregnated with the required substance. Cattle cease to be 

 anno^'ed with flies if washed with a very weak solution of this acid. 

 A valuable salve is also made by adding about sixteen per cent 

 of phenic acid to butter or other fatty matters used for such pur- 

 pose. 



