1799-] 
perth and faid: that fhe had feen an im- 
menfe number of lights. A certain preffure 
and a motion in the nervous: fluid of this 
woman produced therefore in her foul the 
idea of an immenfe number of lights, 
none ‘of which exifted externally. We 
experience the fame thing on receiving a 
violent blow in the face, when we imagine 
we fee a great number of {parks before our 
eyes. Thus different preflures and mo- 
tions may alfo produce different notions, 
which have no external efficient objeé 
The author of thefe ob/ervations experi- 
enced a moft itvriking inftance of this kind. 
He dined once with an old gentleman who 
was a great natural philofopher, and. ftill 
padi of the complete ufe of his intel- 
leétual faculties, notwithftanding his ad- 
vanced age. While the glafs circulated 
cheerfully, and rational mirth prevailed in 
the focial circle, the company was luddenly 
ftartled by the unexpected queftion of the 
old gentleman; what girl that was who 
ftood by the fide of his chair? The guefts 
protefted they faw no girl. However, he 
perfifted in his aflertion, and even began 
to give a minute defcription of her. —The 
image which the old gentleman thought he 
faw, could not poffibly be a bedy really 
exifting out of his imagination, as, in that 
cafe, it mult have been vitible to the 
whole company; becaule every body-re- 
flects rays of light on our eyes, which pro- 
duces the fentfe of vifion. Certain im- 
_preflions or motions muft therefore have 
taken place in the fibres of the brain, or 
the optic nerves of this old gentleman, 
like thofe which are conneéted with the 
image ofa girl. 
Another inftance of this kind happened 
to a friend of the weiter of this article, 
which admits of a fimilar explanation. 
This gentleman, a proieffer of mathema- 
tics at an univerfity in Germany, in whofe 
houfe he lived, came one evening to the 
-writer’s apartment, and related the follow- 
ing fingular circumftance: He had gone, 
late in the evening, into the garden ad- 
joining his houfe, to look at the ftars. 
When he left his apartnient, he faw his 
maid. fer vant fitting wpon a chair, {pinning. 
Having contemplated the ftarry heavens 
fome time, he went back again to his apart. 
ment. When he afcended the ftairs he 
met his maid-fervant, and, on account of 
the narrownefs of the paflage, made room 
for her to pafs by. Conceive, reader, his 
aftonifhment, when, on entering his room, 
the found the fame fervant in the fituation 
in which he had left her, fitting on her 
ee, and [pinning ! What could that ap- 
‘parition have been? Nothing elf ¢ but a 
® Montuiy Mac, No, Li. 
On Apparitions and Secand Sight, 
the ftars. 
78 
renovated ‘vibration of the optic nerves? 
which was fimilar to thatdtafative impref> 
§ion which had been produced in his brains» 
when, on quitting his room, the rays re= 
fluCting from that perion fell upon his eyes. 
This is the more probable, as he had 
{trained his optic nerves in contemplating 
Apparitions ave therefore pofi- 
ble; but they are not what they commonly 
are " fuspofed to be. They are mere illufons 
of the fenfes, aud of imagination : but not 
amages, the objet of tvhich exifis EXTER- 
NALLY. 
The principles with which we have fet 
out in the beginning of thefe obfervations, 
might eafily ‘be applied in explaining the 
numerous inflances of fecond fight, related 
of the Scotch iflanders, and_of the inhahit- 
ants of Worth Wales. However, I fhall 
endeavour to do this ina different way, 
and apply principles which will unfold the 
natural caufe of thefe phenomena in amore 
fatisfactory manner. 
In attempting to point out a natural - 
caufe of the numerous inftances of fecond 
figot, velated of the inhabitants of North 
Wales and the Scotch iflanders, it will be 
neceflary we fhould obferve above all 
things, that fixoke and mifly vapours are 
fufeeptible of the reflexion of the rays of light, 
and capable of producing shadowy images, 
re prefenting figures of human beings, of 
animals, caftles, Gc. Ge. 
In autumn and in fpring a thick fog lies 
frequently towards night, on rivers, bogs, 
morafles, lakes and damp difti&s. IE 
now a perfon*go towards fuch a-place 
covered with mifty vapours, particularly 
in an eatterly direftion, the fhadow of 
fuch. a perfon, or of ether objects behind 
him, may be weflected by fuch vapours, as 
by a mirror, which will make him imagine 
that a isluck man or any other object j is 
coming towards him, and which fuddenly 
difappears when he comes too near the 
place whence this phantom is-formed by 
refietion. Wemay fee the fame pheno- 
menon ina darkened apartment, which 1s 
{trongly fumigated, foas to be entirely fil. 
led madi the imoke as with a fog. If feve- 
ral perfons, the hindmoft of whom carries 
a lighted taper in his hand,-enter fuch an 
apartme nt, the thadows as the foremott 
willbe reflected by the fmoke, and feveral 
black men will feem to be ftanding-in the 
room.’ This apparition diffolves as foon-as 
the foremoft perion takes the candle in his 
hand, becaufe the efficient caule of the re-~ 
flection of the fhade ceafes. 
Watery vapours form a mirror-like fu- | 
erficies, which, if backed by a dark bo'y, 
reprefents a kind of looking glafs that re- 
5 wl flects 

