HARMONIC ANALYSIS AND PREDICTION OF TIDES 109 
moon (s), of the lunar perigee (p), of the sun (h), of the solar perigee 
(p;), and of the moon’s ascending node (N), may be obtained from 
table 4 for the beginning of any year between 1800 and 2000. The 
values for any year beyond these limits may be readily obtained by 
taking into account the rate of change in these elements as given in 
table 1. The corrections necessary in order to refer the elements to 
any desired month, day, and hour are given in table 5. As the tables 
refer to Greenwich mean civil time, the argument used in entering 
them should refer also to this kind of time, and in the lines for the 
beginning and middle of the series at the head of the form space is 
therefore provided for entering the equivalent Greenwich hour. Any 
change in the day may be avoided by using a negative Greenwich 
hour when necessary. For example, 1922, January 1, 0 hour, in the 
standard time of the meridian 15° east of Greenwich, may be written 
as 1922, January 1,—1 hour in Greenwich time, instead of 1921, 
December 31, 23 hour, as would otherwise be necessary. If a negative 
argument is used in table 5, the corresponding tabular value must be 
taken with its sign reversed. For the middle of the series the nearest 
integral hour is sufficient. 
310. The values of J, v, &, v’, and 2v’’ are obtained for the middle 
of the series from table 6, using N as the argument. If N is between 
180° and 360°, each of the last four quantities will be negative, but I 
Form 149 
CNetoumnemew: TIDES: STENCIL SUMS. 
Station sae Marr 0 es OTe rer A ag oer ees .. Lat.:..26°. 22! Me 
ye sea: 16 : wns: 1919 = Feb.=13-0 120° 51° W 
Component: {'3i" .... Length of series: Se Series begins: note etennee. Long. :-6L 92 We 
Kind of time used: ESAS ha PR See .. Computed by Prog Meume LT s_DOG23 s1920e—— 
Pos. = OY 1 2 3 + 6 6 7 a 26 10 VW 
21 2509 18ol 14.8 1465 1006 11.1 1703 2308 2301 2404 2hel 2206 
22 16.8 14.8 Te?  S5e% 606 lel 1905 2302 2605 2706 30.8 24.9 
23 1708 1607 1502 2001 2106 3007 3303 3703 3900 4208 35.9 2804 
PA 7.2 6.8 6:2 6.1 645 8.0 _9e7 10.9 .}8.3 1201 11,0 
Sums=21-24 6707 550% 4508 4604 4505 6009 7908 9502 10609 106.9 99.8 8503 
m 1520 43701 356.3 300.3 28605 323.8 40207 49508 57805 63504 64526 593.5 52304 
Sumse~ 50408 41107 B40 33209 369.1 46206 57506 67507 742035 75205 69303 60807 
Divisore.- 164 163 162 165 164 4165 163 163 164 165 163 162 
Neanse= 3.008 2.63 2012 2202 202d 284 3.53 4:13 4.53 $066 4025 3.76 
21 23503 16.2 17.0 1703. 2303 2400 2807 32.9 3509 4201 Be? Slel 6558.8 
22 2205 2007 2002 2600 2609 3le? 3602 34.0 40.0 31.3 2602 20.5 551% 
23 2501 1665 1565 1166 12.9 1307 1966 2501 2606 2602 24.0 2405 57308 
24 3.3 4.7 3.0 167 009 029 1.7 3.4 5.05 7.0 7.7 7.8 159.8 
Sums 21-24 7202 5909 5507 5606 6300 70.3 8602 954 10800 10606 9206 8309 1843.8 
m 1220 443.6 375-0 518.0 288.9 310.7 388.8 483.6 569.6 613-7 62006 590.7 5}3,9 11093.0 
Sums e= 51508 45409 37307 34505 373507 45901 56708 66500 721.7 72702 68303 59708 1293608 
Divisors.= 162 163 163 163 #162 4162 163 163 + 162 162 163 168 
Means.= 3018 2267 2029 2012 2edl 2.83 5.48 4.08 4.45 4.49 4.19 367 
FIGURE 13. 
