JE S 
iE T H 
JE T I I 
23 
try is synonymous with pneumatics, a term 
iii more common use. See Pneumatics. 
AERONAUTICA denotes the art of sail- 
ing through the air, as a ship in the sea. This, 
however fanciful it was formerly accounted, 
has been lately reduced to a reality. See 
Air Balloon. 
AEROPHOBIA, among physicians, signi- 
fies the dread of air, which is a symptom of 
phrenzy. Dr. Franklin says he has some- 
times been seized with aerophobia, but expe- 
rience soon convinced him that fresh air is 
eminently conducive to health. Any air, he 
says, is preferable to that of a close chamber, 
which has been again and again respired with- 
out change. 
AERO PITY LACE A, a term used by some 
naturalists for certain caverns or reservoirs of 
air, supposed to exist in the bowels of the 
earth, by means of.which they account for the 
origin of springs. 
AEROSTATION. See Air Balloon. 
ERUGINOUS, an epithet given to such 
things as resemble, or partake of the nature of, 
the rust of copper. Thus, an airuginous co- 
lour is green, or that of verdegris. 
rERUGO sads, a kind of reddish slimy 
matter, separated from the Egyptian nutrum; 
probably a mixture of bitumen and a red 
earth. 
ERUSCATORES, in antiquity, a kind of 
strolling beggars, not unlike gi psies, who drew 
money from the credulous by fortune-teliing 
and juggling. 
'i he priests of Cvbele were called cerusca- 
tores mag ace matris, on account of their beg- 
ging in the streets ; for which purpose they 
had little bells thereby to draw people’s at- 
tention to them, much like some orders of 
mendicants abroad. 
Eruscatores was also a denomination 
given to griping exactors, or collectors of the 
revenue. 
ES, properly signifies copper, or money 
coined of tiiat metal. Authors speak of ces 
mule, ces grave, and ces signatum. Some 
suppose the two former to denote the same 
thing, viz. money paid by weight and not by 
tale, as the ces signatum, or coined money, 
was. Others again consider the css grave to 
have been large pieces of coined copper, con- 
taining a whole as, or pound weight. Kuster, 
on the other hand, thinks that ces grave was 
used to denote any kind of copper money, in 
opposition to that made of gold or silver, which 
was light. 
Es jlavum, yellow copper, among the Ro- 
mans, an appellation given to the coarser 
kinds of brass, the finest being called oriclial- 
cum ■ See Brass and Orichalcum. 
Mkis jlos, among antient alchemists, a kind 
of small scales procured from melted copper, 
by exposing it to a vehement heat : but among 
the moderns it is sometimes used for aerugo or 
verdegris. 
Es iistinn, among chemists, a preparation 
of copper, otherwise called ces veneris, ces cre- 
matum, &c, There are several ways of making 
it; but the most frequent is, by exposing 
plates of copper in a reverberatory furnace till 
they will crumble into a powder, which is 
called ces ustum: this is extremely drying and 
detersive, and therefore used for eating off 
dead flesh, and cleansing foul ulcers ; and 
either sprinkled on the part in powder, or 
mixed in ointments. It is also used for co- 
kmring glass. 
Es. Per ass et libra m, was a formula in 
the Roman law, by which purchases and sales 
were ratified. The phrase was originally used 
in speaking of tilings sold by weight, or by 
scales, but it was atterwards used on other oc- 
casions. Idence, in adoptions, the formula 
expressed that the person adopted was bought 
per ass et libram. 
fiESCHY i\ OMENE, or Bastard Sen- 
sitive Blant, a genus of the class and or- 
der diadelphia clecandria. r l he corolla is pa- 
pilionaceous ; and the essential character is, 
calix bilobate, legume with truncate one- 
seeded joints. 
it is a shrubby plant, and includes eight 
species, all exotics. Four species the E. as- 
pera, Americana, Indica, and pumila, are an- 
nual plants. Only two of the species appear 
to be sensitive, viz. the E. Americana and 
sensitive.. '1 lie others are chietiy cultivated 
for their beautiful flowers ; the legumes of 
some of the species are a toot and a halt, and 
two teet, long. The E. cannabina, which is 
a native ut die East Indies, treated as liemp, 
may be used as such. r l hey are ail very ten- 
der stove-plants in this country. 
.ESC ULUS, horse chesnut, a genus of the 
heptamiria monogynia class and order, or the 
natural order of trihilatsr. The essential cha- 
racter is, calyx one-Leated, five-toothed, ven- 
tricose ; corolla five-petailed, irregularly co- 
loured, inserted into the calyx ; capsule three- 
celled. 
The genus embraces three species. The 
common horse chesnut is well known. On its 
first introduction into this country, lather 
more than a century ago, from its very quick 
growth, it was more cultivated than it de- 
served. It is now found that it will seldom resist 
a great storm of wind ; and the very short time 
its leaves continue, renders it unsightly a great 
part of the year ; yet it must be confessed that 
its form is regular, and its blossoms beautiful. 
The wood is of little use but for burning, 
though it is said that it is now employed by 
the turners. The nuts are eaten by deer, and 
Hanbury affirms that hogs will fatten on them : 
Haller also relates, that sheep have been fed 
with them whole, and poultry with them when 
boiled. The yellow and scarlet horse chesnut 
are cultivated for the beauty of their flowers. 
ETATE probanda, in law, a writ which 
formerly lay to enquire whether the king’s te- 
nant was of full age ; but now disused, since 
the abolition of wards and liveries. 
-ETHER, a term used by some philoso- 
phers for the most subtile of all fluids, which, 
commencing from the limits of our atmo- 
sphere, was thought to pervade the vast ex- 
panse of heaven. 
Authors differ widely with respect to its na- 
ture ; some making it a finer kind of air, others 
a kind of fiery effluvium from the sun and fiery 
stars, and others a fluid sui generis. 
Ether is supposed by some philosophers 
not only to fill up tire intermediate space between 
the heavenly bodies, but to permeate all bo- 
dies whatever ; also to be the medium of light ; 
and, lastly, that it was the cause of gravity in 
the earth and other celestial bodies, assisted in 
the action ot burning, and in the dissolution of 
other bodies, by menstruums. After all, mo- 
dern philosophers make it a question whether 
there is any such fluid. 
Ether or Ether, is more particularly 
used for an extremely volatile spirit, made by 
distilling alcohol with an acid, and then pre- 
cipitating the acid gas with an atca’i. 
The properties of the aft her obtained are 
supposed to vary a little according to the acid 
employed: accordingly every particular kind 
is distinguished by the acid "employed in its 
preparation. Thus the aether obtained by 
means of sulphuric acid is called sulphuric 
aether; that bv means of nitrous acid, nitrous 
aether. 
1. Sulphuric aether is usually prepared bv 
the following process : A mixture of equal 
parts of alcohol and snip!. uric acid is put into 
me retort, to which a large receiver is then 
luted. It is proper- to sunound the receiver 
with ice, or at least with cc-id water. Iieat is 
applied ; and as soon as the mixture boils, 
the ather comes over and is condensed, and 
runs in large striae down the sides of the re- 
ceiver. As soon as it amounts to one half of 
the alcohol employed, the process must be 
stopt. 'i he ather thus obtained is not quite 
pure, almost always containing a little sul- 
phureous acid. 
This acid may be separated by pouring the 
ather on a little potass, and distilling it over 
again by means of a moderate heat. Mr. 
Dize affirms that black oxide of manganese 
produces this effect still more completely than 
potass. All that is necessary is, to mix a quan- 
tity of this black oxide in powder with the im- 
pure ather, and to let it remain for some time, 
agitating it occasionally. 1 he sulphureous 
add is converted into sulphuric, and com- 
bines with the manganese. 'I he a ther is then 
to be distilled over by the heat of a water- 
bath. 
r l he separation of the liquid from the sul- 
phureous acid, with which it is mixed, is called 
the rectification of the ether, The usual me- 
thod, and we may add the best, is the follow- 
ing, first employed by Mr. Woulfe : Fill three- 
fourths of a bottle with the impure ather, add 
a little water, and a portion of slacked lime. 
Agitate the bottle with violence, and keep it 
for some time in water before taking out the 
cork. If the smell of the acid is not removed, 
add a little more lime, and agitate a second 
time. Decant off the ather into a retort, and 
distil it over. 
2. Ether thus obtained is a limpid and co- 
lourless liquor, of a very fragrant smell, and a 
hot pungent taste. Itsspecific gravity is only 
0.7581. 
It is so volatile that it can scarcely be 
poured from one vessel to another without 
losing a considerable portion of it by evapora- 
tion. When poured cut in the open air, it 
disappears in an instant, and during its evapo- 
ration produces a very considerable degree of 
cold. If a glass vessel containing water, and 
surrounded with a cloth, is dipt into tether 
two or three times, and the aether each time 
allowed to evaporate from the cloth, the 
water in the glass freezes. In the open air 
aether boils at 98°, and in a vacuum at — 20°. 
Were it not, therefore, for the pressure of the 
atmosphere, it would always exist in the ga- 
seous state. 
It is exceedingly inflammable, and when 
kindled in the state of vapour, burns with ra- 
pidity, with a fine white flame, and leaves be- 
hind it a trace of charcoal. During its com- 
bustion carbonic acid is generated. How 
well soever it has been rarified, it always exhi- 
bits traces of sulphuric acid. 
When aether in the state of vapour is mad® 
