ition to the peculiar tidal régime of the Java-sea, the cotidal lines 
run here very near to each other, by which reason two places, 
situated at no great distance may show very different tidal constants. 
For such stations a simple interpolation with respect to intensity 
or time of occurrence is not allowed, and the determination of the 
characterising constants is of great importance because it is the 
only way of obtaining exact data concerning the manner in which 
tidal waves progress and mutually interfere. 
The observations have been made at the request of Major 
J. J. A. Murrer of the Topographical Service, who wanted an 
exact determination of the general water-level in the bay in behalf 
of the Topographical Survey of South-Sumatra. 
b. The constants of the partial tides Ms, O and N have been 
computed in the ordinary way by arrangement of the records according 
to the different periods; the constants of the other tides Sj, Sj, 4), 
Ks, Sa, Ssa and the value of the general mean W have been cal- 
culated by means of the monthly means. The problem, therefore, 
consisted in computing 15 quantities from 73 equations in the 
simplest and most advantageous manner; it would have been a 
tedious work to apply directly to this problem the method of the 
l. sq. and the results would not have been more accurate than 
by using the following abbreviated method. 
c. The constants of the tides S, and Sz, as also the general mean 
value W, are deduced from the 6 equations given by the hourly 
means taken over the whole year. 
These equations are for the given hours: 
(1) 8 a.m.= W+S, cos (300°—C)) + S, cos (240° — Cy) 
(2) 10 ,, = W+S, cos (3380°—C)) + Sy cos (800°— Co) 
(3) noon = W + S, cos C, +. S, cos Cy 
(4) 2p.m. = W + Sj cos (30° — C,) + Sy cos (60° — C,) > (1) 
(5) 4 „ = W+S, cos (60° — Cy) + Sy cos (120°—C,) 
(6) 6 „ = WJ Sj cos (90° — Cy) + Sj cos (180°— Co) 
Mean : W +- 0.644 S, cos (15°—C)). | 
By combination of (1) with (4), (2) with (5) and (3) with (6) 
S, is eliminated, the result is: 
(1) + (4) = 220.2 e.M. = 29, sin (75° — Ci) sin 45° + 2W 
(2) + (5) = 219.1 ,, = 28) sin (105°—C)) sin 45° + 2W 
(3) + (6) = 218.7 „ = 28, sin (135°—C)) sin 45° + 2 W 
