An easy method of filling long Syphon tubes. 269 
country, before I tried the experiment. The ancients, we know, 
brought water for the supply of their cities, by means of costly ac- 
queducts, over hills and vallies, without ever using the fountain prin- 
ciple. 
About twenty years ago, I suggested to some gentlemen in Boston 
the feasibility of conducting water from one good well to dry reser- 
voirs in the neighborhood, in consequence of hearing that certain 
wells in the city had copious springs of good water, which became 
bad for want of sufficient use. ‘The idea of carrying water through 
a syphon several hundred feet in length, and drawing water from one 
well into another, was discussed by these gentlemen, and treated 
with ridicule. But some years after, Mr. Chapman, proprietor of a 
distillery in Charlestown, requested me to describe the process; and 
with that mstruction he employed a Plumber to lay a leaden tube of 
three quarter inch bore, from a well twenty five feet deep, several 
hundred feet distant from the well of his distillery, which was about 
thirty feet deep, and where he wanted a greater supply of water. 
The operation failed. He then came to me, and told me that I had 
led him into an expensive error. I told him that had he communi- 
cated to me his intentions, I would with great pleasure have super- 
intended the work ; but now, not knowing what defects there might 
be in the tube, I could not answer for his success. However, I con- 
sented to assist him, but my first essay was unsuccessful. 
I need not inform you Sir, as to the principles of the syphon, or 
that its power to overcome an eminence is limited to about thirty two 
feet, answering tothe column of water which the pressure of the at- 
mosphere can raise; or that any defect in the syphon, or any air 
confined in it, would be fatal to its operation. ‘The usual mode of 
charging a syphon, you know, is by exhausting it partially by inspi- 
ration at the longer end. But this was not possible with a tube sev- 
eral hundred feet long, and the expense of a Pneumatic apparatus, 
to procure a vacuum, would have been too great; therefore, I had 
determined to put it in operation by filling it with water, both ends 
being stopped: this was done by a small branch at the summit of 
the tube; and when filled, this branch was well corked, and the cork 
pressed down hard on the water, so as to exclude all the air at the 
surface. It was to be apprehended that some undulations might ex- 
ist in the horizontal part of the tube, and afford a receptacle for air, 
which would there be confined without a possibility of escaping, and 
also prove fatal to the success of the experiment ; but of this I could 
know nothing, as I had not seen the tube laid. 
