394 Miscellanies. 
it never had continued to run over ten days ata time. He had re- 
peatedly taken it up and tried it, supposing it contained a Jeak. He 
called on the man whom he had originally empluyed to lay his pipe, 
for a cause, and found that he knew nothing, except that the stoppage 
was occasioned by air, and that air could not get in, unless there was 
a leak in the pipe. My friend, when I arrived, was taking up his 
pipe for the last time, to try whether there was a leak. After trying 
it with a pressure of 50 Ibs. to the inch, he found no leak and laid 
down his pipe, and by means of a forcing pump set the water running 
again. As formerly, after running less and less for about ten days, it 
entirely ceased. I then took it in hand, determined to find out, if 
possible, the cause of the obstruction. I made a puncture in the pipe 
at one of the high places lower than the spring, and found that the 
pipe contained not air, but hydrogen gas. Iwas now more embarras- 
sed than before, as I could not imagine what was the source of the hy- 
drogen. I happened about that time to take a tin cup of water, and 
noticed a row of minute bubbles along the seam; the thought struck 
me, that it was the combination of metals in the pipe that occasioned 
galvanic action sufficiently powerful gradually to decompose the water. 
To try it, I put a small piece of the same pipe into a tumbler of 
water, and after standing two days, I found the pipe covered with a 
coat of white oxide, with the exception of the seam where it was 
soldered together, and there the tin which composed the solder was 
perfectly bright. From this I inferred, that the galvanic action of the 
“pipe on the water produced decomposition, the oxygen combining 
with the lead, and the hydrogen carried along by the water until it 
came to the high places in the pipe, and there accumulated until it 
filled the pipe and entirely obstructed the water. 
To remedy this difficulty, I made holes into the pipe at every high 
place, and soldered over them a vertical tube, open at the top, excep- 
ting the hill that was higher than the spring, and to that part of the 
pipe I soldered a tube similar to the others, with this exception, that I 
soldered it up atthe top. The first mentioned tubes let the gas escape 
as it came along, and the one on the highest elevation suffered the gas 
to accumulate in it until a small bubble protruded below the end of 
the vertical tube, and was detached from the body of the gas in the 
tube and carried on by the water. After the above arrangement was 
effected, the water was set running, and has continued to run without 
any sensible diminution ever since, upwards of eight months. Query- 
Is not the action of water upon lead, mentioned in Vol. xxx1v, P- 25, 
of this Journal, occasioned by a combination of some other metal with 
? 
Tuscaloosa, Ala. May 25th, 1838. 
en aida nn eit 
