RIO JANEIRO. 71 
Lieutenants Emmons and Underwood, on their first trip, obtained 
many interesting botanical specimens, among them Bromelias, Til- 
landsias, &c. 
On the 16th, the Peacock, with the two tenders, sailed for the 
purpose of measuring the distance between Cape Frio and Enxados 
observatory. I had first determined to measure the distance by 
rocket-signals, as the distance, lying nearly east and west, rendered 
this method very applicable ; but the duties I was engaged in, and 
the difficulties I might encounter from delays, prevented me from 
having recourse to it. I therefore adopted that by sound, wishing 
also to satisfy myself with what accuracy a length of this distance 
could be measured in this manner. 
Captain Hudson was also ordered to examine the St. Thomas 
Shoal, to the northward of the Cape. 
The manner of accomplishing the former duty was as follows. 
The three vessels were anchored in a triangle, with the light- 
house in sight, two vessels being in range with it, nearly east and 
west, towards the harbour of Rio. Each vessel firing four guns, the 
times of the flashes and reports of which w T ere noted in the others. 
The angles were simultaneously observed between the objects, and 
the astronomical bearings taken. This gave the data to connect the 
survey with the light-house. 
The vessels now changed their positions alternately, anchoring in 
range, and on astronomical bearings proceeding westward, until they 
reached the island of Enxados, where they again formed a triangle 
in connexion with the observatory. 
Our repairs in Rio were extensive, particularly those on the 
Peacock. Among other things, the head of the mizzen-mast had to 
be cut off eighteen inches, in consequence of a defect in it, which it 
appeared had been filled up with rope-yarns and putty, and painted 
over, at her outfit. The defects about the vessel were so glaring that 
in going to the high latitudes, it would have been impossible to have 
secured the crew from great suffering and exposure. Even in the 
state in which the squadron was now put, I had every apprehension 
of the greatest disasters. The Peacock, particularly, was wholly 
unseaworthy for such a cruise. 
My object in giving these details is not to impute blame to any 
one, however satisfied I may be of the great neglect in all the 
outfits, but to let the country know what were the difficulties we 
had to encounter. 
