TENDENCY TO CALCULOUS DISEASES. 
61 
Up to the age of 14, the deaths are only 1 in 14^ ; and above that age, 1 in 
Between 14 and 40, the mortality is 1 in 10^ ; but after that period of life, 
it is augmented to the formidable extent of 1 in 3|. 
The number of female cases, in the whole, has been 31 ; the proportion, 1 in 
20 ; and the deaths 1 in 1 But from the improved practice by dilatation, all 
risk of life, in the abstraction of calculi from females, seems to be taken away. 
I have mentioned, in the Medico-Chirurgical Transactions, the removal from a 
female of a calculus of nearly 3^oz. troy, in weight, by spontaneous dilatation*; 
and some examples are given in the Philosophical Transactions, by Dr. Moly- 
neux, Dr. Heberden, and others, of a similar kind : but it was not till of late 
years, that dilatation was employed to supersede the usual operation of litho- 
tomy in women. 
The following Tables will exhibit, at one view, the number of operations of 
lithotomy at the Norfolk and Norwich Hospital, with the mortality, at different 
periods of life. 
Age or Sex. 
Operations. 
Cured. 
Died. 
Mortality. 
Both sexes . . . 
649 
560 
89 
1 in 7-29 
618 
531 
87 
1— 7.1 
Females .... 
31 
29 
2 
1—15.5 
Both sexes. 
Under 14 ... 
292 
272 
20 
1 — 14.6 
14 and upwards 
357 
288 
69 
1— 5.17 
14 to 40 . . . . 
155 
140 
15 
1 — 10.33 
40 and upwards 
202 
148 
54 
1— 3.74 
14 to 50 .... 
196 
171 
25 
1— 7-84 
50 and upwards 
161 
H7 
44 
1 — 3.56 
Under 16 ... 
317 
294 
23 
1 — 13.78 
16 and upwards 
332 
266 
66 
1 — 5.03 
* Vol. vi, p. 574. 
