The enquirer. [volume] (Richmond, Va.) 1804-1815, 1810-10-26

Of person on horseback, at the distance Of y
miles
Mr. Rumboldt lsments that he had not an op.
po-tun'ty of trying, within the tropicks, the pho
tometcr, with which professor Leslie has enrich
ed ojr philosophical apparatus. We heartily join
him in that feeling but we regret still more that
he bad mob employed the hygrometer, which the
same, philosopher has constructed from nice
we w OF the nature of evaporation and which,
combining accuracy of principle with facility of
application, promises, when better understood, &
more generally ddiused, 20 procure incalculsble
advantages to science and to the practice of the
useful arts The hair hygrometer of Saussure,
the most delicate, perhaps, of AL those formed
with hygroscopick substance, can only shew, in
any case. the relative attraction, rs 1T svariOusy
modified, of arr, and of the material itself. for
humidity The instrument, on the summit ofthe
Andes, was found TO mark 400, which quantity
being reduced by correction TO SO, is conceived
to denote most excessive dryness proof suffi-
centy striking, OF the utter ftitllity of the con
tr'vance for, at those vast heights the air
to be constantly charged with vapour; and drift
ing fogs moisteu and refresh the lsnEGid vegeta-
ton of the para,nos, or Alpine deserts. We will
admit, that the capacities of air for heat and
moisture are augmented togt Their, by rarsfaction
Ii an apartment IN Quito were constantly heated
up to the same degree vne at Lima, it would,
no doubt, be much drier; but this disposition is
at hrst counteracted by the cold which prevails
IN the superior regions. The condition OF the'at.
mosphere in regard to humidity, depends on the
opposite influence of two very different laws,
which app, Az TO perform important part in the
economy OF nature. Where the antagonist forces
balance each other, the greatest humidity ex-
lists
This is the proper region ofthe clouds, beyond
which the sky is perpetually clear and serene. In
the vicinity of the Andes, according to Hum.
boidt the large clouds are not seen to rise higher
than 10 or $4,000 feet above the sea but small
MI "A A..., .,-l. l..
sheep, are often observed floating at height of
IS QUO feet. These mountains are moistened with
perpetual dcws Hail and snow fall, in cert ain
seasons OF the year, at the elevation of 1900
icet but, at that of 10000 feet, hail appears, ac-
companied with thunder. The high plain of Mex.
leo is generally dry and psrched, and in many
parts covered with saline efilOrescence. Among
the lower valleys, terrible storms of thunder,
whh torrents OF rain, are frequent during the
night In New Spain, there are only two distinct
seasons the estacion de las agaas, or rainy sea.
son which begins in June July, and ends with
september or October; and the eStio, or dry sea-
son, which lasts during all the rest of the year
The annual fail of rain within the tropcks NAV
be stated at six feet; 1t amounts to eight feet at
Guayaquil.
Uncultivated plains of amazing extent occur
IN ooulh hmerica---Fhe Licnos or savannahs,
when stretch on dead level for hundreds Of
miles south east from The shores of the Orenoc
CO. resemble the placid surface Of the ocean,
lowered with thin layer of vegetable mould &
ied by dews, or deluged by periodical rains. tho
destitute ofsprings or trees, they produce in luz
uriance tall rushy grass, which pastures hume
Ious nerds OF cattle, that, since the conquest of
America, have become wild, and roam i'm a state
OF nature The fautbas OF Buenos Ayres are
pialra OF the same kind, but still more extensive
among these shady flats, packs of dogs, which
nave reiapsed into the savage state, and lodge in
.he notes. rush fiercely from their burrows upon
uie uhwsfy traveller a succession Of plain,
stretches, perhaps beyond the sources of the Gu
aYlari' 10 that vast upland desert, which the ear
~ discoveries of America, viewing as far be-
yoha the DIN ana STIR OF mortais, styled in the
play ofimsgmation, the para,no de Ia su,,,ia eas.
or, !IS wilderness Of Supreme ,eeOse.
All. IT the genial climes of the SOUTH nature
mas poured forth her vegetable productions in
rich variety and splendid profuson. Here is the
reign OF eternal spring and flowers and fruits
cluster the boughS in constant succession No
thing can exceed the beauty and grandeur of the
forests within the terrld zone. Thick intermin.
gled trees, ofmajestic port and each Varied hue,
rear their lofty heads, crowned with odorous
mowers, & spreading with outrageous & resplen-
Gent ioi'age. Creeping plants mantng in rank
iuGurIance, interiace the smooth trunks with end
iess lestoons. Dense woods OF this composition
interrupted only by some rivers, extend over a
space OF more than 800 miles, from the banks
OF the Orenocco to the shores of the Amazons
Inc Chief inhabitants OF these forests are mon.
seyss winch multiply exceedingly among the
iruiiful boughs. Some of them live in pairs me.
isnehoiy, shy, and avoiding even their own spe
ces. Others go in troops Of eighty or hundred.
sPringng from branch TO branch in quest of
food. VI
But the equatorial regions of America, pos
sesslng, IN consequence of their vast range Of
ieSatlon, every possible degree of Temperature
concentrate AL the diversity of the vegetable
tribes. From the shores of the Atlantck TO the
heights OF the Andes, the different kinds of
plants follow each other in almost regular success
SION. Similar transitions, on small scale. are
observed s'nong the Alps Of Switzerland AS.
we meet SUCCESSFULLY with chesnuts, beeches,
OAKS, and then pines, which, covering much
broader space, advance till they become stunteG
ana gradually disappear, not far from the verge
ct perennial snow To trace the geography of
plants IN the low grounds of Europe, is rendered
peculiarly difficult by the activity OF cultivation
Out IN these bonudess deserts, each species still
occupies its own distinct territory. TIE vine oc-
cuples narrow belt towards the north of the la.
titude OF 80 Chesnuts grow IN The same paral-
lei Next succeeds the oak, which extends al.
most TO the Goth degree oflatitude. In this tenn
Perate zone, wheat and barley are cultiyat ed
Oats prefer colder climate but will seldom
thrive beyond the latitude of $50
On this subject, Humboldt has furnished
some valuable remarks. He has also given us
very curious and instructive drawing, which
represents vertical section of the American
continent across the Andes; and exhibits in Z
syuoptlck view, the results Of his various obser-
vations, physical, geological, and botanical -