( 3 l 4 ) 
each Cafe, that I (hall wave it here, and content my- 
felf with (hewing that it may be longer, by an Ex- 
periment that will prefently be made. Another Vari- 
ety in this Sort of Fountains might be made by a fecond 
Feeding-Stream Z, coming into the fecond Refervoir 
E F G H; but the bare mentioning of that will at prefent 
be fufficient. 
If in the Contrivance of a Angle Refervoir and Sy- 
phon, the Stream derived from the Syphon (hould fall 
into another Refervoir Fig. 4. I K K L, having no Sy- 
phon, but only a common Out-let X, and (hould in this 
Refervoir meet and join with another Stream conftant- 
ly running, a Fountain derived from the faid Out-let X 
would be a Reciprocating-Spring; by which Name I 
call thofe Springs which flow conftantly, but with a 
Stream fubjeft to encreafe and decreafe, to diftinguifli 
them from Intermitting-Spring9, which flow and flop 
alternately. And if the Out-let X be too fmall to carry 
off all the Water brought into the Refervoir IKKL, 
by the Syphon, over and above what is brought in 
by the conftantly running Stream W ; then the Sur- 
face of the Water in the (aid Refervoir IKKL muft 
continually rife, ’till the Velocity of the Stream going 
out at X, is fufHciently encreafed, to carry oft' the 
Water coming in : Upon which, the Difcharge of the 
Syphon being continually le(fened,the faid Surface will 
again fubfide, and the Velocity of the Stream atX will 
diminilh j fo that both the Encreafe and Decreafe in this 
Reciprocating-Fountain will be gradual. Befides, if 
the Refervoir IKKL, or the Channel derived from it 
fhould have any Leaks, Crevices, or other Out-lets, 
the Water will iflue through them upon the Rifing 
of the Surface in the faid Refervoir, and occafion 
Springs, which will ceafe again when the Surface fub- 
fides. Let 
