1817.] ; Royal Institute of France. 241 
had been entrusted to him. But this captain sank under the 
fatigues of the expedition. He does not remain to give us an ac- 
count of what may seem inexplicable in his conduct. Were we te 
condemn hiin without being heard, we should expose ourselves to the 
charge of that malevolence with which we stigmatize his memory. 
The second book is devoted to geographical and nautical descrip- 
tions ; that is, to the enumeration of the points perceived, and to 
the mass of observations which time and circumstances allowed 
them to collect on each coast. Here they treat of Van Dieman’s 
Land and of Bass’s Strait. We find a complete account of a great 
land which required two painful and difficult campaigns to explore ; 
interesting discoveries on coasts each more than 300 leagues in 
extent ; curious details-respecting New South Wales, Port Jackson, 
several isles in the great Asiatic Archipelago, particularly Timor ; 
observations of irregular and extraordinary tides, of the declinations 
and inclinations of the magnetic needle; not to speak of a great 
number of nautical and geographical facts, the noticing of which 
would lead us too far. 
The third book gives an analysis of the charts. Here we may 
remark the memoir in which M. Boullanger gives examples of the 
calculations made to determine the rate of the time-pieces, and to 
correct the distance of the moon from-the errors of the lunar tables; 
for these errors, how small soever they may be supposed, have still 
sensible effects upon the determinations, to which we wish to give 
the greatest possible precision. 
The longitudes are fixed relatively to four principal points : 
1. The fort Concordia, in the island of Timor. 2. The point 
Benilong, at Sidney Cove, near Port Jackson. 3. The observatory 
of Bernier, near a cape in the island of Crés. 4. The high point 
on the peninsula of Peron, in the bay of Sea Dogs. These longi- 
tudes were determined by east and west lunar distances for the first 
three, and east only for the fourth. The corrections for the errors 
of the tables were — 14’ 38”, — 13’ 28”, — 13/31”, + 6’ 57”. 
For the north-west harbour (channel of Entrecasteaux) and the 
point Maugé (isle Maria), the corrections were — 17’ 4” and + 
3’ 13”. ‘The intermediate longitudes were calculated according to 
the corrected rate of the time-pieces. 
Very good rules exist for laying down plans and sea charts ; but 
to put them in practice the navigator must be master of the motions 
of Mis vessel. If he has not the chief command, he must be satis- 
fied with taking the best advantage of the situation in which he 
happens to be, and endeavour by the number of his observations to 
compensate for the irregularity of the directions which he receives. 
The directions of the vessels were determined in the usual way, but 
with a care which it would be difficult to surpass. Watches were 
substituted for the sand-glasses, still most commonly employed, but 
the use of which should be entirely stopped. The errors of estima- 
tion have been diminished by all the known methods, and particu- 
ee by those furnished by astronomy and trigonometry. This may 
ov. 1X. N° IID, Q 
