548 PRACTICE OF PHYSIC. 



vals, which in some are exact, in others very irregular. Of the 

 exact intervals there is also a great variety, some returning 

 daily, others in a tertian form, some monthly, others again, an- 

 nually. 



" The consequences of these headachs are frequently one or 

 other of the various disorders of the head, as oblivion, fatuity, 

 and mania. Oftentimes they end in epilepsy, palsy, or apo- 

 plexy : sometimes they fall upon the exterior parts of the head, 

 affecting the senses and their peculiar organs, as the eyes, with 

 more or less suffusion, and often with an amaurosis or gutta 

 serena ; and also the ears, impairing or destroying the sense of 

 hearing. A common effect, where the pain is situated over one 

 eyebrow, is to leave that eyelid paralytic. Frequently the tem- 

 poral muscles are affected with a palsy or atrophy. Such are 

 the chief effects of an idiopathic headach. 



" In order to judge here what are the proximate causes of 

 headach, and how it may operate in producing these topical af- 

 fections, or the disorders attending it, we must enter into the 

 theory of the disease. 



" In the first place, the headach may proceed from simple 

 fulness, and the distention occasioned thereby, which gives the 

 Cephalalgia plethorica. Thus we see it manifestly arising from 

 all the causes which produce or increase a fulness of the blood- 

 vessels, which occasion a temporary rarefaction, or which deter- 

 mine the blood in a greater force, or in a larger quantity, to the 

 vessels of the head. This is sufficiently explained by the oc- 

 casional causes of this disorder which we have already men- 

 tioned. We shall only illustrate it by a single instance of a per- 

 son who laboured under an ascites^ founded on osteosteatomatous 

 tumours, occupying a large portion of the abdomen ; these com- 

 pressing the blood-vessels, produced many various swellings in 

 the vessels of the lower extremities, and a constant fulness in 

 the veins of the head, so as to occasion violent headachs ; any 

 stooping in particular, brought on headach, dimness of sight, 

 giddiness, stupor, partial paralytic affections, and sometimes 

 formal fits of apoplexy, lasting several hours. This shews 

 how the headach may frequently be produced by various in- 

 clinations of the head. This is the most simple view of 

 headach, as depending on plethora, which is often slight and 



