CLASS I. 2. 2. 19- OF IRRITATION. 79 



of the fpine fwells, and rifes above the reft. This is not an un- 

 common difeafe, and belongs to the innutriton of the bones, as 

 the bone muft become foft before it fvvells , which foftnels is 

 owing to defect of the fecretion of phoiphorated calcareous earth. 

 The f welling of the bone compreifes a part of the brain, called 

 the fpinal marrow, within the cavity of the back-bones ; and in 

 confequence the lower limbs become paralytic, attended fome- 

 times with difficulty of emptying the bladder and rectum. 



M, M. IfTues put on each fide of the prominent bone are of 

 eat effect, I fuppofe, by their ftimulus ; which excites into 

 ction more of the' fenibrral powers of irritation and fenfation, 

 nd thus gives greater activity to the vafcular fyftem in their 

 icinity. The methods recommended in diftortion of the fpine 

 re alfo to be attended to. 



19. Spina bifida. Divided fpine, called alfo Hydrorachitis, as 

 well as the Hydrocephalus e,xternus, is probably owing in pare 

 to a defect of offification of the fpine and cranium ; and the col- 

 lection of fluid beneath them may originate from the general de- 

 bility of the fyftem j which affects both the fecerning, and ab- 

 forbent veflfels. 



A curious circumftance, which is affirmed to attend the fpina 

 bifida, is, that on compreffing the tumor with the hand gently, 

 the whole brain becomes affected, and the patient falls afleep. I 

 fuppofe the feme muft happen on compreffing the hydrocephalus 

 externus ? See Sett. XVIII. 20. 



20. Offis palati defeftus. A defect of the bone of the palate, 

 which frequently accompanies a divifion of the upper lip, oc- 

 curs before nativity , and is owing to the deficient action of the 

 fecerning fyftem, from whence the extremities are not comple- 

 ted. From a fimilar caufe I have feen the point of the tongue 

 deficient, and one joint of the two leaft fingers,' and of the two 

 lead toes, in the fame infant ; who was otherwife a fine girL 

 See Sect. XXXIX. 4. 4. 



The operation for the hare-lip is r.efcribed by many furgical 

 writers ; but there is a perfon in London, who makes very ingeni- 

 ous artificial palates ; which prevent that defect of fpeech, which 

 attends this malformation. This factitious palate confifts of a 

 thin plate of filver of the ihape and form of the roof of the mouth ; 

 from the front edge to the back edge cf this filver plate four 

 or five holes are made in a ftraigrft line large enough for a needle 

 to pafs through them -, on the back of it is then fewed a piece of 

 fponge ; which when expanded with moifture is nearly as large 

 as the filver plate. This fponge is flipped through the divifiou 

 ef the bone of the palate, fo as to lie above it, while the filver 



plate- 



