FOUNTAIN. . 
For the Se seg theory, 
agrees fee Spain 
the ancie . the fountains, or feurces of rivers, 
ae “held faered, and even worthi ipped, as a kind of di- 
vinit ies, 
“Seueca’ ents as _ in his forty-firft ep#itle; and 
Cicero, lib. iti. De Nat, » Cap. 20. mentions, that the 
Romau priefts, and cede. “ate d, in their prayers and in- 
“wocations, to call on the names of the "lyber, and othe 
rivers, brooks, and {prings, about Rome.. And 
a m p..g4. of Gruter, has FONT pvivino Er 
G mints FONTIS. 
Tew was a point of religion, not to difturb, or make m uddy, 
.thefe waters in wafhin Tacitus S$ pives an In- 
-ftance hereof in . lib. xiv. cap. 
Fountain, of Artificial Fountain, in 
machine or contrivance, whereby w ater - violently {poute d, 
er darted ap called alfo'a jet d'eau.’ See Jet a’ Lau, 
Fiuip Dd, &e. 
There are divers kinds of artificial fountains; 
“founded on the {pring, or elafticity, of the air ; 
i &e. 
f thefe, being pretty and curious, 
and affording a good illuftration of the os ine of hydraulics, 
and pntumatics, fhall be here explain 
The theory of aie may be colleéied from the ire 
other (gail relating’ to 
ipes of eoadua 
origin, &c. of fprings, or 
2. 
Hydraulics, a 
fome 
and. others, 
ater, 
y be face sider 
but ue oe reich the ie of the velfel ; 
the velfel ses firft half Glled with water. 
at 
out of which. it will Fi itfelf, and emerge into. 
rear iy of the veflel, and lie over the furface of. the 
wa 
Now, the water here pals iat being ae preffed. by the 
air, which is, e. gr. twice as denfe a external air, and 
the elaltic force of air Bene equal * ie paces g force ; 
the cfle&. will be ad fame, as if the weight of ‘the column 
of air over the furface of the water were double that of the 
colum epriiag in a tube ; 2 pe the water muft, of ne- 
_ceffity, {pout roug tube, when the fyringe is 
d, with a force equal . the excefs of preffure of the 
included, above ra thepxt al 
ae 
higher re that w 
fun hath bee 
oy 
g 
thefe vertical tubes, fit other horizontal ones, under aon. 
to carry place where the fountain is to play. 
pee from aay ‘horizontal tubes, ere&t other vertical 
ajutages, jets, or f{pouts, their altitude 
face much’ an than that: of. — ubes whereby the water 
was carried to the horizont 
- Then will the water, by, thes refire al the Auperincum. 
the fe Een 
a 
bent column, be fpouted up = sae jets; 3 and that to the 
of the water in: 
ut 
ent 0 Or ine 
nee at plea- 
loned as to yield any 
made to yield bietg in any 
eee tubes may project 
Rules for all which the | reader 
will find among the laws of Fruips and Juts 2’ Eau 
Thefe aerial or se fountains _may be copied im va- 
rious manners, fo a 
will not be una. 
"OUNTAIN /pouting the water in waricus airedions.—Si 
ofe - vertical Wea or t, in whic ater rife 
P . 
inclining, el ad ng a SOP, MN, 
all water retains ‘he direction 
through a it 
e perpendicularly ; and ae thr ough L Hy, N, P, : 
will saolbag — es of different magnitudes, and tending 
different w 
Or alien : opale the vertical tube AB, fiz. 9. through 
which the water Tiles, t to be i {topped at the top, as in A; 
ets, let it 
through the little 
nce proportional to the height of 
hence, ad the tube A B a8 a te the mre oF 
en pe be nifhed with an nium, or coc’ 
i ae op sac the ee = ran aes vill be ee un- 
peCtedly w 
“ mutt be ae obfer a = ei diameters of the a aper- 
tures i which the water is e muit be confiderably 
lefs than thofe of the tubes in “which the water is ee ; 
left the refiftance of the air, and other im pediments, fpe- 
cay under -ounD and Jer Paw break ae force of the 
j ie edi Beaying by the Ga . ne the breath.— Seip. 
eA fs, or metal e fphere, wherein 3 18 
ing a ttle acy in C, 
and the orifice C be im- 
sek immerged under cold i the water will afcend 
ough the ere into the {phere 
eeding, by repeate ted exfuctions, till the veffel 
0 water; and then:applying the mouth 
‘upon removing the 
phere be be poe in ir water, 
wi 
This Paces me 
-ball, fom = na 
the air, being 
e water {pout as before.- 
d Pila 
a Heronis, or Hero’ s 
me aa its inventor. 
whereof 
chee d'pl 
ball. a a Bollow brafs bal ae Yer 2 oF a tafe 
up ang 
Hence, 
