513 
On the day of Mrs. Kirwan’s death, 6th September, 1852, the moon’s 
age at noon was 21.9 and her declination 20° 1’ 54” N. The tide of 
the evening of this day is, therefore, comparable with that of the morning 
of the 18th September, 1851, when the moon’s age at midnight preceding 
was 227.1, and her declination 19° 51’ 14-8 N.° 
Calculating the times of high water, low water, and half ebb, from 
the Academy’s observations at Kingstown for the 18th September, 1851, 
I find that on the evening of the 6th September, 1852, 
High water at Ireland’s Eye occurred at 4" 37™ Pp. uw. 
ow, Water a. ls) Soi eels wun ame eel Olena 
5 UN af) 0] ON Raa aa Misael ge ahawe a5s 
and that the range of the tide on that day was only 6:7 ft., the moon 
being in the commencement of her fourth quarter; and, therefore, the 
tide being neap. Introducing into the tidal observations at Kingstown 
the difference between the top of the ‘‘ Body Rock” and the zero of the 
gauge, or 6°864 ft.,—I find the following Table to give the true heights 
of the Tide at Ireland’s Eye on the 6th September, 1852, referred to 
the ‘‘ Body Rock”’ as the zero; and I have placed beside the true heights 
the heights alleged in Court during the trial of Mr. Kirwan. 
Heights of Water above Top of ‘‘ Body Rock,” 6th September, 1852. 
bed 
Height al- 
Time. True Height. leged Difference, 
: in Court 
High Water,| + 4°84 ft. 147-00 ft.| + 26-0in. 
6'30P.mM./+ 3°11 ,,/+2°50 ,,/-— 73,, 
TiO Gyg oP DEST,» WT Toke, 
17:15 ,, |+1°85 ,, |+1°375,,|— 5°7,, 
7°30 ,, |+1°384 ,,}+1°00 ,,/— 4:0 ,, 
Low Water,|—1°86 ,,;—2°00 ,,{]-— 1°7,, 
Fortunately for the interests of justice, the time of Mrs. Kirwan’s 
death coincided very nearly with the time of half ebb of the tide, 7° 
25", p.u., when the real height of the water above the ‘‘ Body Rock’’ 
only exceeded that alleged on the trial by 5 inches. Had the critical 
moment been near the time of high water, the evidence given would 
have been in error by upwards of 2 feet; and as the exact height of the 
water was considered of great importance by both the Crown and the 
prisoner’s counsel, a substantial injustice would have been done to one 
side or the other by the admission of erroneous evidence on a scientific 
question of so great delicacy and importance. 
Some remarks were made by Professor Hennessy, Charles Davis, 
M.D., Robert Mallet, Esq., and Sir Henry T. Brownrigg. 
Mr. Haughton explained. 
R. I. A. PROC.—YOL. VII. 4¢ 
