626 PHILOSOPHICAL TRANSACTIONS. [anNO I762. 



great portion of it be lost, it is supplied again, sooner or later, and the patient 

 recovers his sight. 



Dr. C. saw Daviel extract the crystalline quite opaque, with its whole bag ad- 

 herent to it ; and this bag he dissected from it after the operation was over. In 

 the operation of the 14th instant, the crystalline and its whole bag made one en- 

 tire spheroid, soft and plump; but it is already broken and dry. 



Blue eyes are the most subject to the cataract, and black ones to the amau- 

 rosis. In these the ciliary nerves and fibres are always weak ; in those strong 

 and elastic. 1 . A crystalline couched, if the capsula be opaque, leaves the patient 

 blind. 2. A crystalline couched in appearance, if it adheres in any point to its 

 capsula, must rise again. 3. If the posterior side of the bag be opaque, and 

 remains, the patient must remain blind, whether the crystalline be couched or 

 extracted. 4. If the posterior side of the bag is adherent to the crystalline, it 

 must be extracted; and then there is great danger of the vitreous humour coming 

 off. 5. The mistakes of Sennertus, Riverius, Heister, Antoine, Maitre Jean, 

 Brisseau, and St. Ives, &c. about the glaucoma, are easily accounted for in this 

 new theory, founded on facts and daily experience. 



LXXXIll. On the Case of Mortification of Limbs in a Family at fVattisham, 

 Suffolk. By Charlton fVollaston, M. /)., F.R.S. p. 523. 



John Downing a labouring man at Wattisham, in Jan. 17 62, had a wife and 

 6 children; the eldest, a girl about 15 years of age, the youngest about 4 months. 

 They were also at that time very healthy, as the man himself and his neighbours 

 assured Dr. W. 



On Sunday the 10th of January, the eldest girl complained in the morning of 

 a pain in her left leg; particularly in the calf of the leg. Towards evening the 

 pain grew exceedingly violent. The same evening another 'girl, about 10 years 

 old, complained of the same violent pain in the leg. On the Monday the mother 

 and another child, and on the Tuesday all the rest of the family, except the 

 father, were affected in the same manner. The pain was exceedingly violent; 

 insomuch that the whole neighbourhood was alarmed with the loudness of their 

 shrieks. The left leg of most of them was only affected ; but in some both legs. 

 The little child was taken from its mother's breast as soon as she was taken ill, 

 and lived a few weeks. The nurse told Dr. W. it seemed to be in violent pain, 

 and that its legs were black before death. 



Dr. W. was exact in his inquiries about each particular person. By what he 

 could learn from them, in about 4, 5, or 6 days, the diseased leg began to 

 grow less painful, and to turn black gradually ; appearing at first covered with 

 spots, as if it had been bruised. The other leg began to be affected at that time. 



