.1816.} Royal Institute of France. - 148 
always sufficient. It is seldom the most convenient for the calcu- 
lator. We may even sometimes doubt whether the figures have 
been transcribed and engraved with the requisite exactness, 
Notwithstanding these difficulties, we have satisfied ourselves that 
the south dial was very exact. The height of the style ought to be 
64 English inches. This value has been directly verified six 
different ways ; we may say by the whole details of the dial. The 
hours are temporary, and are not numbered. 
The northern dial is only a supplement to the first. It is on the 
same scale, and had the same style. We see only two lines of the 
morning and two of the evening; or rather those lines which pro- 
ceed from the bottom of the style indicate the direction of the 
shadows for these different instants. ‘Two of these four lines are too 
long, because, instead of the hyperbolic arc, which ought to ter- 
minate them, a straight line has been drawn. These slight faults 
are but of inferior importance. 
The east dial plate is not less exact than the south, It is pretty 
narrow, though the length of the style has been 194 English inches; 
that is to say, almost double. This length has been verified by a 
number of particular proofs, and by the whole of the dial. 
The dial of the south-west offers the same agreement in all its 
parts. The height of its style must have been 251 inches. The 
inclination of the equinoctial with the horizontal is 42° 40’, just 
what calculation gives. 
The dial of the, north-east does not appear to have been con- 
structed with so much care, or at least so successfully. The style 
is only 62 inches. The horary lines, only three in number, are 
very oblique. The least error in the graphic operation may sensibly 
alter these lengths, and these considerations excuse the artist. Be- | 
sides, . this dial is the least important of all. We here see nothing 
which we may not obtain with much more certainty from the neigh- 
bouring dials. : 
The three other dials, those of the south-west, the west, and the 
north-west, could only offer the counterproofs of the opposite dials, 
The author has not figured them in his plates. In general, he is 
frugal of information respecting these dials, which interested him 
less than what concerned architecture. But he has ‘done all that 
we could demand in giving us the exact figures of five dials, which 
offered something particular: these dials do not inform us of any 
thing which we might not have concluded as well from the dial of 
Delos; but they are much larger, and better executed. They are 
in their place, and in all respects form the most curious monu- 
ment that we know of the practical gnomonics of the ancients. 
The following is a list of the works published by the’ members 
of the Institute in the course of the year. 4 
Travels to the Equinoctial regions of the new Continent, in the 
Years 1799, 1800, 1801, 1802, 1803, and 1804, by Alea, de 
Humboldt and A. Bonpland; drawn up by Al. de Humboldt ; with 
4wo Allasses, which exhibit, the one the Views of the Cordilleras 
