164 REPORT—1840. 
on, and the causes rendering the amputation necessary, whether from 
disease previously existing or from accident. Some of these results 
were as follows: of the 276 cases, 216 were males, of whom 86 died ; 
60 were females, of whom 14 died ; 153 were from previous disease, of 
whom 35 died. In operations at the shoulder the deaths were equal to 
the recoveries ; of the arm, the deaths to recoveries were as 3: 14; of 
the leg, as 1:2; at the wrist, at one period, as 1:29; in another pe- 
riod as 8: 22. 
On Opacity of the Cornea produced by Sulphurie Acid. 
By R.D. Tuomson, M.D. 
The rapid destruction of vision, when sulphuric acid is brought into 
contact with the cornea, has long been known to surgeons. ‘The sub- 
ject came under the author’s consideration from having attended a 
case along with Dr. Maddock, in which the vision of the right eye was 
destroyed, in consequence of a woman having thrown a quantity of oil 
of vitriol at a man in a fit of passion. The corrosive fluid, according 
to the statement of the sufferer, was only in contact with his eye about 
two minutes, when he had an opportunity of washing it off with water ; 
yet permanent opacity of the cornea had taken place. It naturally 
occurred, from a consideration of this statement, that the agency of 
the acid could not have extended to any very considerable depth. 
The anatomical structure of the cornea likewise favoured this conclu- 
sion. The author described the laminar structure of the cornea, and 
the additional investment of the conjunctiva, and drew attention to the 
effects of heat, nitrate of silver, &c. on these structures. When sulphu- 
ric acid or common oil of vitriol is brought into contact with the dead 
cornea of the sheep, in three or four seconds, if the experiment be 
watched under the microscope, the acid, which appears to swim about 
freely on the surface of the cornea, produces a milkiness; in half a 
minute a white opacity ; and in from one and a half to two minutes all 
translucency is destroyed. If the cornea, which has been previously 
extended on glass, be now plunged into water and washed free from 
sulphuric acid, a permanent opacity will be found to have taken place, 
precisely as in the case of those unfortunate individuals who have been 
deprived of vision by sulphuric acid in the manner already described. 
If we now make a section of the cornea which has been acted on by 
the acid, we shall find that the action has been very superficial, and 
that the upper and under surface of the opake portion are parallel, 
and hence the influence of the acid would appear to have extended 
equally. If the section be now made at right angles to the axis of the 
eye, so as to separate the opake from the uninjured portion, the trans- 
parency of the cornea appears to be perfectly restored, and the only 
defect, when a careful examination is made by the microscope, appears 
to proceed from the uneven surface produced by the section. But the 
opake portion may likewise be readily separated by scraping it with 
the point of a knife, so decided is the limit between the uninjured and 
opake surfaces. It would appear from these facts, that the action of 
