On Egyptian Ophthalmia. 329 



If instead of taking the forces in angular succession, any 

 other order had been observed, the rt-suhing force would 

 bxive been precisely the same: as if -the (>rder had been SA, 

 SCj SD and SB, the figure would have been SAcc/d, 

 wherein Ac is parallel and equal to SC; cd, parallel and 

 cquel to SD ; and c? d parallel and equal to SB; showing 

 the equivalen. force Sd the same as before. 



Demonstration. Draw the lines S b and So; by the 

 compobiiion of forces S b is equ.valent to ihe forces SA 

 and SE. Also S c is equivalent tn S b and SC, and there- 

 fore also to the three forces SA, SB and SC ; also Sd is 

 equivalent to Sc and SD, and therefore equivalent also to 

 ihe four fnn-es SA, SB, SC, and SD. 



A number of useful corollaries might hence be drawn ; 

 but having already exceeded the limits I first proposed, I 

 subscribe myself, 



Sir, your most obedient servant, 



Soho, near Birmingham, JoHN SOUTHERN. 



March 1, 18 13. 



JjI. OnEgypiian Ophthalmia. By William Adams, £5^. 

 Surgeon and Oadist. 



To Mr. Tilloch, , 



Sir, — X HE violence and extensive dissemination of the 

 purulent inflammation of the conjunctiva, under the appel- 

 lation of Egyptian ophthalmia, has made it too genciallv 

 known to require now any description of it; and though 

 it has certainly become less destructive since very copious 

 bleedings have betn employed, vet it has stldoni, if ever, 

 been completely subdued at its commencement *f)y this or 

 any other practice. Under this state of practical know- 

 ledge, in the treatment of a disease, tiie rapidity of whose 

 progress professional men have such frequent occasion to 

 witness, it became a desKlcraiuin to obtain some rcmi.-dial 

 process which should arrest the morbid actions before the 

 eye had sustained any serious injury. The success which has 

 attended a mode (;f treatment suggested by me for several 

 persons labouring under this disease in the St. I'ancras work- 

 house, has made me hope that this desideratum is now ob- 

 tained. 



"Ww Egyptian ophthalmia had existed, in a most active 

 and virulent state, among tiie childrt-n in the al)ove ista- 

 bhshmcnt, for nearly two years j and had infected the at- 

 tending surgeon and the nurses. During ihi- period, the 

 modes of treatment recommended m the publication of an 



eminent 



