I. —Astronom ic Observations. 
The expedition of H.R.H. was supplied with four pocket chronometers at 
mean time, and before starting on the journey these were kept under control 
at the Hydrographic Institute. During this period of control, the absolute and 
daily corrections recorded for the said chronometers at 0 h of mean Greenwich 
time yielded the following results :— 
Place. 
Date, 
1906. 
Mean 
time. 
Lange 
56,509, 
K,. 
K, 
Lange 
56,520, 
k 2 . 
k 2 . 
Longines 
560,229, 
k 3 . 
Longines 
560,234, 
K*. 
k 4 . 
Note. 
Genoa 
20 Feb. 
n°'3 
+ 9*-87 
s 
-23 s -73 
s 
-12 s -43 
-30 s -S3 
-0-27 
-0-57 
+ 1-77 
+0-91 
26 „ 
11 *4 
8 '26 
-0-32 
27 U4 
-0-78 
- 1 -79 
1 ‘65 
25 '39 
1-91 
3 Mar. 
12 -4 
6 *66 
-0-15 
31 '04 
-0-69 
+ 6 '46 
2-03 
15 -84 
1 -12 
8 „ 
14 -1 
5 '93 
-0-41 
34 -47 
+ 0U7 
+ 16 -38 
1-16 
10 -22 
1-09 
13 „ 
14 '6 
3 '88 
-0-45 
33 '62 
-0-60 
+ 22 -68 
2'88 
4 *77 
0-50 
19 „ 
14 -0 
1 -20 
+ 0'20 
37 -20 
-1-07 
39 '95 
2-67 
1 -80 
0-32 
24 ,, 
12 -4 
2 -22 
+ 0-01 
42 -53 
-0-96 
53 -32 
2U3 
0 U8 
0*40 
29 „ 
11 -o 
2 -29 
-0-11 
47 ’31 
+ 0-11 
1“>- 3 s '99 
2U9 
1 '84 
-0U3 
3 Apr. 
— 
1 -74 
+ 0-63 
46 *76 
-0-29 
1 U4 '94 
2-81 
1 -19 
+ 1-00 
In pocket. 
7 „ 
— 
4 -29 
+ 0-29 
47 '99 
-0-07 
1 '26 *19 
5-34 
5 19 
-4-38 
Naples 
14 „ 
6 '38 
47 '52 
2 -04 -68 
36 '88 
In train. 
After leaving Genoa, and more particularly during the voyage by steamer 
from Naples to Port Said, the chronometers were left unregulated. But at 
Port Said they were again set going, and on 20th April, 1906, compared with 
the chronometer at the Police Station, in order to record their absolute 
correction. 
On the 26th of the same month another comparison was effected at 
Jibuti with the chronometer of The Elpliinstone of the Indian Navy, and on 
4th May, yet another with the chronometer of the Post Office at Mombasa. At 
Entebbe, thanks to steps previously taken, it was found possible on 12th May 
to make a fresh comparison by wire with Mombasa, so that by means of these 
two comparisons was obtained a first diurnal correction of the chronometers to 
be used in the subsequent calculations. 
The elements of comparison appear in the record of the pocket chrono¬ 
meters included in the present Report. From it we find that at Mombasa, on 
4th July, at noon, local time, there were the following absolute corrections on 
Greenwich mean time : 
K x = + 3 h 16 m 34 s - 9 
Iv 2 = + 3 26 9-0 
K, = + 3 2 10-5 
309 
