Water Power

Before the introduction of steam engines in the early 1800s, work was completed by human or animal strength or with wind or water power. Water was the most consistent possible power supply and essential for operating any kind of heavy machinery.

 

To supply the water to power the wheel, mills or factories were built where there was a reliable, powerful flow of water, like where a stream descended a slope. To create power, the water would run past a wheel, pushing and turning shafts connected to belts and pulleys that delivered power to machines. The belts and pulleys could be set up in many different ways depending on the layout of the site and the machinery being powered.

 

The Armory site was a good site for water power because of the small natural waterfall where the Mill River meets the low ridge that connects the higher outcrops of East Rock and Mill Rock. The first water-powered industry on the site was grist milling (the production of flour). A grist mill operated there from 1630 until the 1780s. By Whitney’s time, a six-foot-tall timber dam augmented the natural waterfall and created a mill pond for more consistent water supply.

 

The first water wheels at the Whitney Armory were undershot wheels, powered by water running below them. By the 1830s, there were two large iron undershot wheels operating at the site, both fourteen feet in diameter and six feet wide.

 

CAPTION: Basic operation of undershot water wheel. Malcolm Boura, Wikimedia Commons.

 

 

Water from the Mill River and the mill pond powered machines across the Armory site, including the main Armory building and the forge. An archaeological dig in the 1970s revealed the path of the forge tail race, which returned the water to the Mill River near the island.

 

As the Armory grew and its machinery became more complex, its original timber dam, small millpond, and undershot waterwheels struggled to provide enough power. Additionally, the Mill River was overtaxed by the proliferation of factories upstream, and at the Armory it was tidal, meaning high tides could prevent the wheel from turning and stop production.

 

Eli Whitney Sr. made improvements to the dam and the waterwheels in the 1820s. When Eli Whitney Jr. took over operations of the Armory in the 1840s, he was dismayed to find the water supply was again insufficient. He built wheel housings to reduce the problem with the tides, but the factory still needed more power.

 

In 1848, Eli Whitney Jr. installed a more efficient system: a vertical impulse wheel, an early type of water turbine. This machine turned sideways, rather than up and down, and was contained in an iron housing sunk in the ground. Placed away from the Mill River itself, it did not interact with the tides. It was far more compact - 4 feet in diameter, versus the previous 14 foot undershot wheel - but much more efficient. Even so, as the Armory continued to advance, the water power still wasn’t enough.

 

The new 38.5 foot dam of Lake Whitney, built in 1860, provided much more water to power the Armory as well as creating a reservoir for New Haven’s drinking water. The Armory installed penstocks, large iron pipes, to channel water to its improved turbines. One of those penstocks is still visible at the EWMW site, though it has been moved to the Water Lab from its location closer to the dam.

 

The Armory and later occupants of the factory site continued to improve the turbine system as technology advanced. Water power was used at the site until 1933, when the last of the machinery was converted to electrical power. The final turbine building can be seen between the Water Lab and the dam.

 

[LEARN MORE: LINK TO Windows on the Works ARTICLE PDF]

 

[LEARN MORE: GEOLOGY AND THE QUARRY]