4 i8 DISEASES Class IV. 2. 2. V* 



The late Dr. Monro afferted in his lectures, that he cured the 

 hemicrania, or megrim, by a ftrong vomit, and a brifk purge 

 immediately after it. This method fucceeds beft if opium and 

 the bark are given in clue quantity after the operation of the 

 cathartic ; and with (till more certainty, if bleeding in fmall 

 quantity is premifed, where the pulfe will admit of it. Sec 

 Seel. XXXV. 2. 1. 



Mr. 3£ellie afferts, that fome kinds of head-achs, efpecially 

 thofe which arife from defect of flimulation, may be cured by 

 comprefling the two fubclavian arteries, as they pafs over the 

 firfl rib ; which he thinks would produce a preffure on the brain 

 fimilar to that, which may be produced by the centrifugal force, 

 if a perfon was to lie acrofs a mill-ftone as it revolves. See 

 Suppi. I. 15. 7. Would fuch a circulating bed remove any 

 kind of head-ach ? 



The pain generally affects one eye, and fp reads a Ititle way 

 on that fide of the nofe, and may fometimes be relieved by prefT- 

 ing or cutting the nerve, where it pafTes into the bone of the 

 orbit above the eye. When it affects a fmall defined part on 

 the parietal bone on one fide, it is generally termed Clavus hys- 

 tericus, and is always I believe owing to a difeafed dens mola- 

 ris. The tendons of the mufcles, which ferve the office of 

 maflication, have been extended into pain at the fame time that 

 the membranous coverings of the roots of the teeth have been 

 compfefled into pain, during the biting or maflication of hard 

 bodies. Hence when the membranes, which cover the roots of 

 the teeth, become affected with pain by a beginning decay, or 

 perhaps by the torpor or coldnefs of the dying part of the tooth, 

 the tendons and membranous fafcia of the mufcles about the 

 fame fide of the head become affected with violent pain by their 

 fenfitive affociations : and as foon as this affociated pain takes 

 place, the pain of the tooth entirely ceafes, as explained in the 

 fecond fpecies of this genus. 



A remarkable circumflance attends this kind of hemicrania, 

 viz. that it recurs by periods like thofe of intermittent fevers, as 

 explained in the Section on Catenation of Motions ; thefe peri- 

 ods fometimes correfpond with alternate lunar or folar days 

 like tertian agues, and that even when a decaying tooth is evi- 

 dently the caufe ; which has been evinced by the cure of the 

 difeafe by extracting the tooth. At other times they obferve 

 the monthly lunations, and feem to be induced by the debility, 

 which attends menflruation. 



The dens fapientire, or lafl tooth of the upper jaw, fre- 

 quently decays firft, and gives hemicrania over the eye on the 

 fame fide. The firft or fecond grinder in the under-jaw is lia- 

 ble 



