1806.) 
tom of the veffel. Sauffure doubtlefs had 
not obferved this excels of weight, fo op- 
pofite to that of a vegetable powder, which 
is {pecificaily lighter than. water ; but this 
is the only one of its charaéters which is 
in oppofition to its other fenfible proper- 
tics. On being expofed to a flight degree 
of heat, ic exhales fometimes a {mell like 
that of opium, and at others, fimilar to 
that of plants belonging to the chicorace- 
ous tribe ; when the heat is augmented, 
it {wells and bubbles up like vegetable 
fubftances, diffufing the odour pecuiiar 
to them. | 
“¢ So far my experiments tended to con- 
firm the opinion of Saufiure; but it re- 
mained to be demonttrated whether the 
places where this powder was found might 
not throw fome light upon its origin. I 
was then engaged in botanizing on the 
higheft of the Pyrenean mountains. For 
feven years I had been occupied in this 
purfait, and during that period had col- 
fected from fifteen to eighteen handred 
f{pectes: thefe I carefully examined, and 
can fafely affirm that I did not meet with 
any whole pollen anfwered, either by its 
colour or abundance, to the phenomenon 
in quettion. 
** Bat, on the other hand, Sauffure hay- 
ing at fir endeavoured ta d-feover the 
oiigin of this powder in the mineral king. 
dom, afferted that the coloured fhow was 
not furmounted by any rocks whence it 
could proceed ; and it fs in this refpe& 
that my refults differ from thof of that 
philofopher. 
“The firft time I noticed this appear- 
ance, which was about feven years ago, I 
was ina country abounding with granite ; 
the fnow was detached from the rocks by 
a partial thaw, but it was evicent it had 
once been in clofe contaS with them ; 
and at the origin ofall the furrows, which 
carried down the colou ed powder, I 
found vety dark red grains, whence the 
tint evidently proceeded. What was my 
aftonifhment when, ch examining them 
more narrowly, I dilcovéred them to be 
fall particles of mica, in a ftate of fin- 
gular decompofition, This was not a 
fimple oxidation of the iron contained in 
the mica, but a complete transformation 
of the whole fubltance into a light, red, 
and pulverulent matter. 
particles were completely changed, while 
others of them were bet fuperficially =l- 
tered. T feieéted thefe lat, and feraped 
off the powder with which they were co- 
vered. This was really the colouring 
powder cf the inow, and this fubftance, 
the ‘mineral origin of which was thus 
Many of thele, 
Proceedings of Learned Societies. 539 
proved, affumed a vegetable character in 
my crucible. 
“On the following year, I found the 
red {now on the mountains inthe form af 
micaceous {chiftus. Since which I have 
frequently difcovered it, and always on 
lands abounding with mica. Once, in 
particular, I received a very furprifng 
and unexpected confirmation of this fact. 
On afcensing Mont Perdu, and the far- 
rounding teruury mountains, I discovered 
the rofe tint on the {now which covered 
the glacier of Tuque Rouye. Can this 
phenomenon, faid I to myflf, proceed 
here from any other caufe? Oa examin- 
ing the rocks, however, allthe hard grey 
ftones were in‘ermixed with almoft impers 
ceptible particles of mica. 
<¢ Taftly, the abfence of mica is alone 
fuficieut to explain why Sauffure had not 
obterved the red colour of the fnow on the 
fummit of Mone Bla:c: he bimfelt in- 
forms us, that the granite was there to. 
tally free from any mixture cf mica. 
«© But this laft proof is fupériluous, 
fince | have already fhown that the pro- 
duétion of the red powder in queftion did 
not depend on the prefence of mica alone, 
but required the concurrence of certain 
circumttances which could only take place 
in the middle regions of thefe mountains. 
Sauffore availed himfelf of that confider- 
ation in order to fupport his ootnion, 
while, in fa&, it tends to corroborate 
mine ; fince it is not the prefence of mica 
alone which is neceflary to produce the ef 
feé&t of which we have been fpeaking, but 
a concurrence of particular feafons and 
temperature, joined to a proper degree of 
oxigenation in the fhow, and a certain 
deoree of a€tivity in all the caufes which 
tend to produce this phenomenon : it is 
‘particularly evident in thofe places, and 
during that feafon, in which the elements 
mot ftronely tend to form new combina. 
ticns. Nature, indeed, appears equally 
incapable of producing it at thofe im- 
menfe heights where her energies are en- 
chained by a perpetual winter, or in the 
lowelt rezions where they aré exhanfted 
by fuccellive vegetation. 
“<< On the whole,’ concludes. M.-Ra- 
mond, ‘* from the fa&s I have ftated re- 
fpecting the converfon of mica into a 
powder which acquires al] the charaéters 
of a vegetable produ&tion, it #ppears co 
me to open a vaft field for inquiry; re- 
fveCting the means employed ‘by nature in 
the fucceflive produéticn of organized bee 
ings from the molecules of inanimate 
matter.” 
4 522 ACADEMY 
