Description of a Totally Beflecting Priam. 283 



of fistula, the knotty question as to the existence and situation 

 of an internal opening can hereby be cleared up. Search being 

 made in the manner above described, and with the joint advan- 

 tage of touch and sight, the internal opening, if there be one, 

 can scarcely fail to be detected ; and when discovered, attempt 

 might be made to seal it by the cautery or caustic before hav- 

 ing recourse to a serious operation. Thanks to Mr Listen and 

 Dr Pagan, the practicability of effecting the occlusion of even 

 large fistulous openings by such applications is no longer a 

 problem ; and there is no need of argument to prove the 

 immediate mitigation of fistula in ano which must follow 

 upon shutting off its communication with the interior of the 

 bowel. Thereby the noisome character of the disease would 

 be removed, the constitution would be relieved from the 

 irritation of a foul discharge, and the case be at once con- 

 verted into a simple abscess capable of going through a mild 

 process of healing. It will be obvious, from an inspection of 

 Fig. 5, that by means of the pinching-screw I, the outer prism 

 and its connecting-ring p may be applied to any other size of 

 speculum ; and the handle m, which is made to unscrew, may 

 be fixed in any of the holes n formed in the ring for that pur- 

 pose, should it be found convenient to alter its position or to 

 transfer it to the hand of an assistant without removing the 

 instrument. 



It is unnecessary to multiply illustrations of the simple me- 

 thod of observation explained in this paper, and I would only 

 remark, with reference to the speculum for the uterine pas- 

 sage, that by this way of obtaining observation in the diseases 

 of females, the withdrawn position of the light is calculated to 

 lessen the misery to them attending all professional interfer- 

 ence. In such cases, by having a prism appended to the glass 

 aperture of a small lantern, the patient's apartment might be 

 darkened to any desired extent. 



It may be, that my confident anticipation of adapting the 

 prism to the examination of the avenues meeting in the throat, 

 have led me to use expressions which to some may savour of 

 hyperbole. If I have exposed myself to such a charge, the 

 inaccuracy is unintentional, and the instruments produced 

 afford ready opportunity of testing the characters ascribed to 



