324 
REV. S. HATTGHTON ON THE TIDES OF THE 
Neaps. Range. 
30th May 12-0 inches. 
12th June LL-3 „ 
Mean . . 11*65 „ 
Substituting these values in (6) and (7), we find 
2(M'+S') = 21*5, 
2(M'— S') = 11*65, 
and, finally, 
®=0-297 (9) 
It will be observed that the Diurnal Solar Tide Eange, already determined (9-40 in.), 
bears a very large proportion to the Semidiurnal Tide Eanges. 
C. Diurnal Tide (Times). 
The following Table contains the hour in local time of High Water and Low Water, 
and also the Lunitidal Intervals at High Water and Low Water elapsed from the 
Moon’s passage of the meridian of the place. The Diurnal Tide in time might be cal- 
culated from the Lunitidal Intervals by first or second differences, as in the case 
of heights ; but it is not worth the trouble to make the calculations, as the results can 
be more readily obtained by plotting the Lunitidal Intervals carefully to scale. 
When this is done the diagram shows a fairly regular Diurnal Tide, with vanishing 
epochs and range well marked. 
The maximum accelerations and retardations of the time of High or Low Water 
occasioned by the Diurnal Inequality amounted, generally, to from 35 minutes to 
40 minutes, and on 1st July, at Low Water, reached 65 minutes. 
D. Semidiurnal Tide (Times). 
Northumberland Sound. — Lunitidal Intervals. 
High. Water. 
Low Water. 
High Water. 
Low Water. 
1853. 
k m 
k 
m 
li m 
1853. 
h 
m 
k 
m 
k m 
May 27- 
4 0 p.m. 
-0 
46 
June 1. 
2 
40 
A.M. 
6 38 
27- 
10 0 „ 
5 14 
1. 
8 
32 
„ 
+o 
12 
28. 
4 40 a.m. 
-0 
37 
1. 
3 
30 
P.M. 
7 10 
28. 
12 5 p.m. 
6 48 . 
1. 
9 
40 
„ 
+ 0 
56 
28. 
4 0; „ 
-1 
41 
2. 
3 
30 
A.M. 
6 46 
28. 
11 0 „ 
5 19 
2. 
9 
40 
„ 
+ 0 
39 
29. 
4 30 A.M. 
— 1 
38 
2. 
4 
20 
P.M. 
7 31 
29. 
1 0 P.M. 
6 52 
2. 
10 
30 
„ 
+ 1 
5 
29- 
6 0 „ 
-0 
32 
3. 
4 
35 
A.M. 
7 10 
29. 
Midnight. 
5 28 
3. 
10 
30 
„ 
+0 
48 
30. 
6 40 A.M. 
-0 
15 
3. 
5 
0 
P.M. 
GO 
30. 
1 40 p.m. 
6 45 
3. 
11 
0 
+ 
O 
54 
30. 
7 0 „ 
-0 
19 
4. 
5 
0 
A.M. 
6 54 
31. 
12 50 a.m. 
5 31 
4. 
10 
48 
+ 0 
24 
31. 
8 0 „ 
+0 
on 
4. 
5 
30 
P M. 
7 6 
31. 
3 30 p.m. 
7 52 
5. 
12 
15 
A.M. 
+ i 
27 
• 31. 
9 0 „ 
+ 0 58 
5. 
5 
30 
” 
6 42 
