OBSERVATIONS. 
479 
6. Captain Trotter, on being asked 
wbat remaining contingencies on this 
head were to be expected, so far as 
he could now calculate them, men- 
tioned that as there were apparently 
some rocks at Boussa, which it would 
be easy and desirable to remore, in 
order to clear the passage, he should 
require blasting tools for that purpose. 
Item 1st. He estimates the 
blasting tools at about . J014O 
Item 2nd. Diving-helmet 
and apparatus < . 100 
Item 3rd. He thinks it 
would be expedient also to 
have instruments for examin- 
ing the channel, and deter- 
mining points of shoals and 
shores; and he estimates 
these, on the computation of 
Captain Beaufort, at 100^. for 
each vessel , . . 300 
Item 4th. He estimates 
the expense of journey of the 
Commissioners to Liverpool 
and elsewhere on service, at 200 
Item 5th. For additional 
fittings in the cabins for the 
Commissioners, he requires 
about .... 117 
and Oldfield to the Ni- 
ger, extreme inconveni- 
ence was occasioned by 
the bad ventilation of the 
vessels. Good ventilation, 
is, therefore, an impor- 
tant point to provide for. 
70^. have already been 
expended, but not 
paid on this service. 
Carried forward 
. £857 
