140 AERO 
the firft who brought paffive exercife into practice, which 
was afed after fevere illnefs, in order to conquer debility, 
and invigorate the fyftem by gentle means. 
^EQUANA JUGA, mountains of Picedum, in the 
kingdom of Naples, now called Montagna di Sorrento, 
denominated from the town Equa, which being dedfoyed, 
was replaced by Vicus, now Vico di Sorrento. 
.ERA, f. in chronology, a fixed point of time from 
whence any number of years is begun to be counted. It 
is fometimes alfo w'ritten in ancient authors era. The 
origin of the term is contefted, though it is generally al¬ 
lowed to have had its rife in Spain. Sepulveda fuppofes 
it formed from A. ER. A. the notse or abbreviatures of 
the words, annus erat Augujli , occafioned by the Spani¬ 
ards beginning their computation from the time their 
country came under the dominion of Auguftus, or that of 
receiving the Roman calendar. 
The difference between the terms atra and epoch is, that 
the aeras are certain points fixed by fome people or nation, 
and the epochs are points fixed by chronologifts and hido- 
rians. The idea of an aera comprehends alfo a certain 
fucceflion of years proceeding from a fixed point of time, 
ijnd the epoch is that point itfelf. Thus the Chriftian 
aera began at the epoch of the birth of our Saviour Jefus 
Clirift. 
jERARIUM,/. the treafury or place where the public 
money was depofited amongft the Romans. 
j^rarium Sanctius contained the monies ariling 
from the twentieth part of all legacies: this was kept for 
the extreme neceflities of the Hate. 
.Erarium Privatum was the emperor’s privy purfe, 
or the place where the money ariling from his private pa¬ 
trimony was depofited. 
tErarium Vicesimarum, the place where the mo¬ 
ney ariling from the taxes levied from foreign countries 
was laid up, fo called becaufe it molt commonly confided 
of a twentieth part of the produce. 
Erarium Ii.iTHY.ffi, or Junonis Lucin^, was 
where the monies were depofited which parents paid for 
the birth of each child. 
There are feveral other treafuries mentioned in hiftory, 
as the AErarium Juventutis, Veneris, ( 3 c. The temple of 
Saturn was the public treafury of Rome, either becaufe 
Saturn firft taught the Italians to coin money, or, which 
is molt likely, becaufe this temple was the ftrongeft 
and molt fecure, and therefore the fitted place for that 
purpofe. Erarium differs from /feus, as the firft con¬ 
tained the public money, the fecond that of the prince. 
LOGY. 
The two are, however, fometimes indifcnminately ufed 
for each other. 
ERARIUS,y] a name given by the Romans to a de¬ 
graded citizen, who had been druck off the lid of his 
century. Such perfons were fo called becaufe they were 
liable to all the taxes, without enjoying any of its privi¬ 
leges. 
Erarius was alfo an officer indituted by Alexander 
Severus, for the diftribution of money given in largelfes 
to the foldiery, or people. Erarius was likewife ufed for 
a perfon employed in coining or working brafs. Thefe 
are fometimes called ararii fufores: at other times, cerarius 
is diding'uifhed from /{for; the former anfwering to what 
we now r call copperfmiths, the latter to founders. Era- 
rius was likewife applied to a foldier who received pay. 
AERIA, or Eeria, the ancient name of Egypt: the 
fcholiad on Apollonius Rhodius, fays, that not only Thefi- 
faly, but Egypt, was called Hep ta, by the Greeks, which 
Eufebius alio confirms; and hence Appolinarius, in his 
tranflation of the 114th Pfalm, ufes it for Egypt. Heyf- 
chius applies this name to Ethiopia. ** 
AERIAL, adj. \aerius, I.at.] Belonging to the air, as 
confiding of it.—Vegetables abound more with aerial par¬ 
ticles than animal fubffances. Arbuthnot .—Produced by the 
air. Inhabiting the air. Placed in the air. High; ele¬ 
vated in lituation, and therefore in the air. 
AER 1 ANS, in church-hidory, a branch of Arians, 
who, to the doctrines of that feCt, added fome peculiar 
dogmas of their own ; as, that there is no difference between 
bilhops and prieds; a doctrine maintained by many mo¬ 
dern divines, particularly of the prelbyterian and reform¬ 
ed churches. The feet received its denomination from 
Aerius, an Armenian pried of the fourth century. 
AERIE, J. \_airic, Fr.] Is a proper term for hawks, 
which for other birds is called a neft. The liberty of 
keeping aeries of hawks was a privilege granted to great 
men : and the preferring the aeries in the king’s foreds, 
was one fort of tenure of lands by fervice. 
Flos ER 1 S,/ among alchemids, fmail fcales procured 
from copper melted by a ftrong heat; it is fometimes ufed 
for aerungo or verdegris. 
AEROGR APHY,yi [from ar,f. air, and yp«©«, I de- 
feribe.] A defeription of the air or atmofphere, its limits, 
dimenlions, properties, &c. This amounts to much the 
fame with aerology, unlefs we fuppofe the latter to enter 
into the rationale, and the former to confine itfelt to a de¬ 
feription of the more obvious affections thereof. See 
Atmosphere. 
AEROLOGY. 
A EROLOGY, f. [arp, and Myo^ Gr.] The doftrine 
orfcienceof Air, its nature and different fpecies, 
with their ingredients, properties, phenomena, and ufes. 
Air, in a general fenfe, is that invifible fluid every-where 
furrounding this globe; on which depends not only ani¬ 
mal but vegetable life; and which feems, in fhort, to be 
one of the great agents employed by nature in carrying on 
her operations throughout the world. 
Though the attention of philofophers has in all ages 
been engaged in fome meafure by inquiries concerning the 
nature of the atmofphere, yet, till within thefe lad thirty 
years, little more than the mere mechanical aCtion of this 
fluid was difeovered, with the exidence of fome anoma¬ 
lous and permanently-eladic vapours, whofe properties 
and relation to the air we breathe were almod entirely un¬ 
known. Within the above-mentioned period, however, 
the difeoveries concerning the condituent parts of the at¬ 
mofphere itfelf, as well as the nature of the different per¬ 
manently-eladic fluids which go under the general name 
of air, have been fo numerous and rapid, that they have 
at once raifed this fubjeft to the dignity of a Science, and 
now form a very confiderable, as well as important, part 
of the modern fyflem of natural philofophy. 
Thofe difeoveries, indeed, have not been more intered- 
ing to philofophers, than ufeful to fcience and beneficial 
to fociety. Many perplexing proceffes in chemidry have 
been explained in confequence of them, feveral have been 
facilitated, and a number of new and ufeful ones have 
been introduced. The phenomena attending metallic cal¬ 
cinations and reductions have been greatly elucidated. 
The 
