I C II T H 
the fight. Such of thefe vefiels as T could diftinftly per¬ 
ceive, I judged to he fo (mall (meafuring them by my eye) 
that if one of the globules of blood from whence its red- 
uefs proceeds, were to be divided into a thoufand parts, 
not one of thofe parts could pafs through thefe wonder¬ 
fully thin and flender vefiels. From thefe obfervations I 
concluded, that this fubftance only anfwers the purpofe 
of a membrane or {kin lying next to the fcales ; and that, 
when an eel is creeping through a narrow pafl'nge or hole, 
.a part of this membrane or cuticle, which we call dime, 
is rubbed off in the paffage; and that when eels are kept 
in. any kind pf v eft el without water, and in their motion 
wear off this cuticle, they cannot long furvive ; and, 
Upon my' talking over this fubjeft with a filhmonger, who 
was a very intelligent man in his bufmefs, he confirmed ail 
that I have here mentioned. Further, I imagined that 
this cuticle or Ikin fo covering the fcales of eels, and in 
fome fort proceeding from the fcales themfelves, and the 
vefiels which in a great meafure compolb that (kin which 
we may imagine to be dime, extend fo-far and wide, that 
the vefiels proceeding from one fcale fpread over more 
than twenty-five others, and that this is the reafon why 
this (limy matter covering the fcales is fo thick and tough. 
But, not yet fatisfied with thefe obfervations, I endea¬ 
voured to find out the vefiels in the fcales from whence 
thefe (limy excrementitious vefiels were formed ; and, in 
order to exhibit more plainly the rough or wrinkled make 
of the fcales, I have eauled an exceeding fmall particle 
of one to be delineated, the appearance of which, by the 
microfcope, was that of a lucid or bright cryftal, both 
within and without. This is fliown at fig. 2, I K L M, 
wherein the fide IM reprefents that part which was fixed 
or rooted in the fifh, being about the length of two com¬ 
mon grains of fand. I have fometimes divided the fcales 
of this fifh into fmall parts, and I alway's found that, 
though the wrinkles in them appeared very pellucid, they 
were compofed of nothing but thofe inconceivably-flender 
ftreaks, or rather vefiels, mixed and twifted one within, 
another, as is in fome fort represented in this figure by the 
letters KLN. 
“Some years after the preceding obfervations were pub- 
lifhed, I received from a perfon of fome note in this city, 
a parcel of fcales taken from a very large carp which had 
been kept in his fiih-pcnd, and was fo tame that it would 
take food out of a perfon’s hand. But in the time of a 
ievere froft, the gardener being employed in breaking the 
ice with a hatchet, to givefrefh air to the fifh in the pond, 
this carp came to the hole, and unfortunately received a 
wound from the hatchet, which occafioned its death. 
This fifh was in length 42 inches, and in circumference 
at the thickelb part of its body 33I inches. In order more 
eafily to cut one of thefe fcales in pieces, I fteeped it in 
warm water, and then I cut off a (lice from it, paffing 
through that part where the firfi: formation of the fcale ap¬ 
peared, which original fcale was very minute; and I then 
cbierved forty rows of fcales lying one on another, or, in 
other words, this lingle fcale was a clufter of forty other 
fcales lying on one another. For every year a new fcale, 
forr.eiohat larger than that immediately preceding it, is added to 
the number, and is as it were glued to the former ones ; therefore 
as many of thefe fcales as arc found thus joined together, fo 
many are the years of the fifths age. This affertion of mine 
is however violently contradifted, becaufe many people 
think that I cannot by any means prove what I affirm. I 
determined therefore, to cut off a flice from this fcale 
very obliquely, whereby the rows of the component fcales 
might be more clearly difeerned, and I caufed a drawing 
of this to be made from the microfcope, which is fliown at 
fig. 3, A B CD; the part reaching from A to B, or from 
JD to C, denotes the difference in fize by which each 
newly-formed fcale exceeds that of the preceding year; the 
whole thicknefs of the fcale, as it appeared through the 
microfcope, is the fpace between B and C, but in faff, the 
real thicknefs, as feen by the naked eye, is no more than 
that of a hog’s briftle. 
Vql.X. No. 710. 
Y O L O G Y. 749 
Another piece of the fame fcale, cut ftill more ob¬ 
liquely, I placed before another microfcope, a drawing of 
which is given at fig. 4, E F G H. The fpace between E 
and F is the thicknefs of the fcale ; and as many divifions 
or rows as are there pictured, fo many of the fmall com¬ 
ponent fcales lie heaped one on another, (at lealt as far as 
the limner was able to obferve them,) and fo many years 
had elapfed between the formation of the firfi fcale and all 
the others which were added to it. 
“This cutting or dicing off pieces from the fcales, does 
not fucceed equally well in all, for fometimes their thin- 
nefs caufes it to fail ; but, if the extremity of each fcale 
can but be perceived, the age of the fill) may be gathered 
from it with little danger of miftake. In order to fhow 
this irregular kind of feftion, I caufed a fmall piece of 
that defeription to be drawn from the microfcope, and this 
is fhown in fig. 5, IKLM; here the additional fcales 
produced every year, fometimes appear of a darker (hade 
than they are in reality, and therefore the yearly increafe 
in fize feems represented at IO and MO, but the addition 
of three years’growth'appears at IOK. At fig. 6, be¬ 
tween P and Q, is fliown the natural fize of the flice or 
piece of fcale reprefented, when magnified, at fig. 4. 
“Since we now find that the fcales of fifhes are every 
year augmented in the way I have been deferibing, we 
may form a pretty good judgment as to the time when 
this augmentation is made, by analogy to what we obferve 
in the other productions of nature ; and thence we fhall 
conclude, that the additional fcales are completed at that 
feafon when the .further growth of the fifh is fufpeuded. 
For this is evident in trees, at leaft fiuch as grow in thefe 
regions. The like alfo is the cafe in regard to cows, for 
between certain fpaces of time, when their growth is in¬ 
termitted or ceafes, and when itr again returns, it is fliown 
in the horns ; whence we gather, that, as many knots or 
rings as are found on the cow’s horn, fo many years of 
age is the animal. And, though this may not appear ex¬ 
actly in.the fame manner in all creatures, yet we mull; al¬ 
low that Inch a diftinguifliing circumftance exifts ; and 
this is proved in the falling off of the hair from animals, 
and the fliedding of -feathers by birds, at certain regular 
periods.” 
The dietetical ufes of fifliesare to us the mod important 
article of their hiffory, a part that is happily free from 
that uncertainty and darknefs in which many other cir- 
cumftances relating to their manners and ecopomy are 
ftill involved. All fifli whatever, and particularly thofe 
without the tropics, are capable of being converted into 
wholefome food. Every European fifh, while in feafon, 
is nutritive; the various methods of preparing and drefl- 
ing them are detailed by the authors to whom that pro¬ 
vince belongs. Such difquifitions conftitute the hiffory 
of an art, but they are not the objects of fcience. See the 
article Fishery, vol. vii. p.406. 
Fifties, in general, when out of feafon, are unwbolefome, 
and even pernicious ; and this is more efpecialiy the cafe 
with the oily kinds ; fuch as the herring, the mackarei, 
the eel, and the falmon. So little is this faCt attended to, 
that the eating of the latter of thefe fifties,at an improper 
feafon, has been the immediate caufe of an epidemic fe¬ 
ver. Some of the fifties that frequent the fhores of the 
Weft-India iflands, are alfo pernicious in certain circum- 
ftances. 
Fifh being a very confiderable article of food, and con- 
fequently of commerce, it may be worth while to enquire 
into the practicability of tranfporting certain fpecies of 
them into places where they do not naturally breed. And 
firfi: it is to be remarked, that fifhes are lefs fenfible of a 
change of climate than quadrupeds and birds. For ex¬ 
ample, if you bring a fifh from a warm country, where 
the water never freezes, into a cold one where the dream 
is covered with ice, it will partly avoid the inconveniences 
of the change by remaining at the bottom; and all coun¬ 
tries furnifh, in certain feafons, warmth enough for the 
purpoles of emitting the fpawn of tidies and bringing it 
9 E to 
