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HINTS TO TRAVELLERS. 
Tables V. and VI.—Table V. contains the approximate times of tlie 
meridian passages of 50 of the principal stars for the 1st of the month. 
To find the time of passage on any other day, subtract the portion of time 
corresponding to the day of the month in Table VI. from the time in 
Table V. As the times given in these tables are apparent , they mnst be 
converted into mean time by applying the equation of time as directed 
in Table II. should the mean time of meridian passage be required. 
The result arrived at by the use of these tables is only approximate, but 
will seldom be as much as 2m. in error. 
N.B.—The altitude of any star when passing the meridian may be found 
by adding together the complement of the latitude of the place of observa¬ 
tion and the declination of the star, when they are of the same name, 
or taking their difference when of contrary names; the altitude to be 
reckoned from the south point of the horizon when the latitude is north, 
and the contrary when south; but when the sum exceeds 90° it is to be 
taken from 180°, and the altitude is to be reckoned from the north in 
north latitude, and the south in south latitude. When using the 
artificial horizon, the altitude to which the index of the sextant is to be 
set must, of course, be double the altitude found by this method. 
Table VII. contains the refraction for the barometer at 80 inches, and 
Fahrenheit’s thermometer at 50°. The two small tables at the side 
contain corrections when the barometer differs from 30 inches or the 
thermometer from 50°. 
Table VIII. exhibits half the time that a celestial body continues above 
the horizon when the latitude and declination are the same name; or 
below it when they are contrary names, and affords the means for com¬ 
puting the rising and setting of the sun, moon and stars, and the length 
of the night or day. 
To find the time of the sun's rising or setting , enter Table VIII. with 
the latitude and declination, and the tabular value will show the apparent 
time of the sun’s setting when the latitude and declination are the same 
name, or of its rising when the latitude and declination are of contrary 
names, and this, subtracted from 12 hours, will give the apparent time 
of the sun’s rising in the former case, and of its setting in the latter. 
Double the time of rising will give the length of the night. 
Double the time of setting will give the length of the day. 
Example .—Required the (apparent) time of the sun’s rising and setting, 
