800 
PATHOLOGY. 
Under this genus, Dr. Good includes all difeafes of the 
eye, except Ample ophthalmia. We regret that we can¬ 
not in this place enter into an account of thefe maladies. 
When, however, it is confidered, that the anatomical de¬ 
tails, as to the ftriidture, into which we mud firft enter, 
would be long, and that moreover the mod comprefled 
accounts of ocular maladies occupy a fpace much greater 
than could be introduced into this article, we are com¬ 
pelled to podpone the fubjedt until we arrive at the arti¬ 
cle Surgery. In the mean time we have much fatisfac- 
tion in referring our readers to two works of the fird ex¬ 
cellence for all necedary information upon the difeafes in 
quedion. We allude to the works of Mr. Travers and 
Dr. Vetch. Dr. Good’s cladification of thefe difeafes, in 
which there appears no fault except that catarrh, glauco- 
fis, &c. cannot be confidered as nervous difeafes, is as 
follows. 
r. Paropfis lucifuga, night-fight: vidon painfully acute 
in a drong light; but clear and pleafant in a deep diade 
or the dude of the evening. Chiedy common to thofe 
who live almod condantly in dark inclofures, as mines 
or prifons ; or who have recently had a cataraft depred'ed 
or extraCIed ; and to fhort-fighted perfons. Found alfo, 
cccadonally, as a fymptom in ophthalmy, irritation of 
the optic nerve, and Hydrops capitis. 
a. Paropds no&ifuga, day-fight: vidon dull and con¬ 
fided in the dude ; but clear and powerful in broad day¬ 
light. It proceeds ufually from a want of futficient irri¬ 
tability in the retina; which, in confequence, is only ex¬ 
cited to adlion by a ftrong ftimulus, or ppwerful light ; 
and hence does not clearly difeern in the diade or to¬ 
wards the clofe of day. Hens are well known to labour 
under this defeft ; and hence they cannot fee to pick up 
fmall grain in the dude of the evening, and fo employ 
this time in going to rood: on which account the dif¬ 
eafe is fometimes called hen-blindnefs. 
3. Paropfis longinqua, long-fight: vidon only accu¬ 
rate when the objeCl is far off. 
In the preceding fpecies the hebetude deems chiedy to 
appertain to th 0 retina : in the prefent fpecies it belongs 
chiefly to the iris, which is habitually dilated, and 
not eadly ftimulated to a contractile aClion. For “it is 
well known,” obferves Dr. Wells, “ to thofe who are con- 
verfant with the faCts relating to human vidon, that the 
eye in its relaxed Hate is fltted for diftant objects,and that 
the feeing of near objects accurately is dependant upon 
mufcularexertion.” (Phil.Tranf. 1811,art.xix.) There 
are three varieties, 
a. Vulgaris: common to every period of life, and 
chiefly produced by habitual relaxation of the iris, moft- 
jy with fomewhat too flat a cornea. 
/ 3 . Paretica : from partial paralyds : as an abfolute in- 
con tra&ility of the iris, by which the diameter of the pu¬ 
pil is rendered unchangeable, and a pareds of feveral 
other mufcular powers of the eye is fuperinduced ; while 
the retina continues perfeftly fendble to tire ftimulus of 
light. For cafes, fee Phil. Tranf. 1793 and 1811. 
7. Sene&utis : from old age, in which the cornea ufu¬ 
ally grows lefs convex ; and hebetude and relaxation be¬ 
come common to all the powers of the eye. 
4. Paropds propinqua, lhort-fight: vidon only accu¬ 
rate when the objeCt is near. Mice are fuppofed to have 
this kind of vidon naturally ; and hence the name that 
has been given to it of myopia, or moufe-dght. 
5. Paropfis lateralis, fkew-fight. In this fpecies the 
patient can only fee obliquely, in confequence of fome 
partial obfufeation of the cornea (ufually perhaps from 
fcratches or flight fears), or of the humours through 
which the light is tranfmitted; or from a partial paralyds 
of the retina. This mull not be confounded with ftra- 
bifrnus, or fquinting, which proceeds from a different 
caufe, and is accompanied with different phenomena. 
In lateral vifion, the axis of the eye affeCted ufually coin¬ 
cides with that of the found eye, though it runs fome¬ 
what obliquely to avoid the obftruCtion in the tunic. In 
Jlrabifmus, the two axes do not coincide, and the judg¬ 
ment is formed from the ftrongeft eye alone. If, however, 
in lateral vidon, the obftruftion be fuch as to make the 
optical axis of the affefled eye at variance with that of 
the found eye, fquinting muftbe a neceffary confequence 
of the difeafe. 
6. Paropfis illuforia," falfe dght: imaginary obje&s 
floating before the dght; or real objeCts appearing with 
imaginary qualities. Dr. Good notes two varieties, and 
feveral fub-varieties. 
a. Phantafmatum : ocular fpeftres, affuming various 
femblances; as, dark fpots, the rnufdae volitantes of va¬ 
rious authors; net-work, fparks, dazzling, iridefcence, 
&c. “ Thefe appearances (fays Dr. Young) are fome¬ 
times, if not always, occadoned by an opacity of fome of 
the veflelsof the vitreous humour, near the retina. They 
are feen in a full light; and cannot, therefore, as Sauva- 
ges has juftly remarked, be caufed by any thing in the 
anterior part of the eye ; and they may often be obferved 
to change their form with the motions of the eye ; which 
they could not do if they did not depend on fome float¬ 
ing fubftance. Their apparent change of podtion, when 
we attempt to follow them with the eye, is a necedary 
confequence of the motion of the eye itfelf which contains 
them. 
/ 3 . Mutationitis: real objeCts changed in their natural 
qualities : hence proceed, error of form, when objefts 
appear too large, too fmall, cut in half, diftorted ; error 
of motion, which condfts ufually in dancing, nodding, 
or rapid fucceflion ; and error of number, when objeCts 
are doubled, tripled, or othervvife increafed or multiplied. 
7. Paropds caligo, opake cornea, or web-eye : dimnefs 
or abolition of dght from opacity of the cornea, or fpots 
upon its furface. “ This is the foul flend, Flibbertigib¬ 
bet : he gives the web, and the pin, fquints the eye, and 
makes the hare-lip.” Shukefpeare. 
8. Paropds glaucods : dimnefs or abolition of dght 
from opacity of the humours. 
9. Paropfis catarafta, cataraCf: dimnefs or abolition 
of fight from opacity of the cryftalline lens. Three kinds. 
a. C. lenticularis, lenticular: the opacity exifting in 
the lens itfelf, and confined to it. 
/ 3 . C. capfularis, capfular or membraneous: the opa¬ 
city confined to the capfule, or membrane of the lens. 
7. C. complicata, complicated : the opacity common 
to the lens and its capfule. 
10. Paropfis fynizefis : dimnefs or abolition of fight* 
from contraction or obliteration of the pupil. Two va¬ 
rieties. 
a. S. flmplex, dimple clofure of the pupil. The pupil 
becomes clofed or obliterated from progreflive contrac¬ 
tion, and at length coalition, of the mufcular fibres of 
the iris; from inflammation of the furrounding mem¬ 
branes ; or from protrufion of the iris. In all thefe cafes 
it is called “ dimple obliteration of the pupil.” 
( 3 . S. complicata; clofure of the pupil complicated with 
cataraft or an opake cornea. 
11. Paropfis amaurofis, gutta ferena, or drop ferene: 
dimnefs or abolition of fight, with an unalterable immo¬ 
vable pupil, ufually black and dilated ; but without any 
other apparent defect. Three varieties. 
a. A.atonica; with permanent atony and dilatation 
of the pupil. 
| 3 . A. fpafmodica ; with permanent contraction. 
7. A. intermittens; with periodical ceflations and re¬ 
turns. 
is. Paropfis ftaphyloma, protuberant eye : enlargement 
of the ball of the eye; protuberance of the cornea; dght 
dim or abolilhed. Staphylo 7 im is from oTatpvX-n, a grape, 
on account of tla,e refemblance of the tumour to the pul¬ 
py and femi-tranfparent appearance of this fruit. Rich¬ 
ter has the credit of having firft pointed cut the real na¬ 
ture of this difeafe, of which there are three varieties. 
a. St. fimplex; from increafed fecretion of the aqueous 
or other humour: pupil tranfparent. 
j 3 . St. 
