I have 100' of that out behind the barn. I should go see what kind of condition it is in and see if people here want them.
A few notes about poultry nipples:
They are used at low pressure. They are normally run after an adjustable pressure regulator at a few PSI, do not hook them directly to a garden hose run from the house, you'll make a mess. Gravity feed should work fine.
If you trigger the nipple with your finger and let the water run off your finger, the minimum flow for a medium sized (4 lb) layer in moderate weather should be 1 to 2 drips a second, increasing with larger birds / hotter weather. (In my experience anyways, your mileage may vary). On a gravity fed system you can increase the flow by raising the supply container, thus increasing pressure. In a layer house, the pressure (thus flow rate) would be adjusted to keep the litter from becoming neither too wet, nor too dry and dusty.
A nipple for every 8 to 10 birds is adequate.
Proper height depends upon the height of the birds. For chicks the nipples should be at eye level, older birds should stretch their neck and peck at the nipple at a 45 deg angle. If they are pecking straight in or straight up (on nipples without cups) they'll get water everywhere.
Nipples are sensitive to sediment and hard water. Check them regularly for proper operation.