108 
HINTS TO TRAVELLERS. 
to observe rays is beyond the limits of his last sheet, and that none 
of his fixed points will fall upon it. 
In this case he must assume a convenient point on his board as his 
position, turn the board in a suitable direction with regard to what 
he wishes to do, and sighting, if possible, one of his old stations, draw 
a line towards it. Should another former station be visible, another line 
should be drawn to it. The magnetic meridian must also be drawn by 
means of the compass. These three lines will enable him to place his 
new sheet in proper relation to his former one-, by arranging them with 
the meridian lines parallel, and moving one until the continuation of the 
lines passes through the two former stations. They can then be pasted 
together in that position, joining them by another strip of paper, if 
necessary. 
Even should there be no fixed stations in view, rays drawn to objects 
he wishes to fix will be useful, always supposing that he can afterwards 
fix the position by rays drawn from other stations, never omitting to 
place the magnetic meridian on the sheet. 
New bases must occasionally be measured, and it will be found that 
one of the chief charms of such surveying lies in surmounting difficulties 
in the construction of the map. Devices for so doing will suggest them¬ 
selves in increasing numbers as the traveller gains experience. 
Though reliance on the compass should be avoided if possible, from 
its uncertainty, owing to local attraction, recourse must frequently be had 
to it, and under favourable circumstances, plane-tabling by its aid gives 
excellent results. 
Concluding Remarks .—On leaving a station, the traveller, when possible, 
should leave some distinguishing mark behind him, so that he may be 
able to recognise it again. Where it is possible, as will frequently be the 
case, he must carefully note the changes which take place in the 
landscape during his march; he will also do well to write on the plane 
table sheets the native names of such hills, or conspicuous objects, as 
he may have fixed on the table, as natives generally know these objects 
again when viewed from another station, which, from their changed 
appearance, a stranger would be very unlikely to do. Paper mounted 
on very thin cloth, and cut to the size of the plane table, will be found 
serviceable, as it will not easily tear, and can be rolled up and kept in 
a tin case until wanted. The traveller should also provide himself with 
