- The Amador Canal and the Impulse Turbine OR How Samuel Knight Created Hydro-Electric Power

The Samuel Knight Shipyard on the Presumpscot River. A hydro-electric plant later built on the shipyard site is shown here. From a map by Ford S. Reiche of Falmouth Maine Gravity creates water pressure. Drawing Andy Fahrenwald Knight Wheel Collection of Robert Johnson Pelton Wheel Mechanical Engineering, June 1939 Doble Wheel Transactions of the American Institute of Mining Engineers, Vol. XXIX, 1899 Donnelly wheel displayed by Donnelly Foundry workers. Courtesy Amador County Archive Knight Wheel in foreground, Knight Foundry on the far right, Consolidated Eureka Mine's mill across Sutter Creek, shortly after 1872. Note pipe running from left to wheel, and flume returning exhaust water across creek to mine flume, probably supplying a traditional overshot water wheel to power the mill. Courtesy Amador County Archive Water-powered newspaper Courtesy Amador County Archive Water-powered mine hoist plan Collection of Robert Johnson Knight's first Dynamo Motor for Amador Electric Railway & Light Co. Collection of Robert Johnson Pioneer Power Plant in Odgen Utah Collection of Robert Johnson Penstock descending to Electra Power House PG&E of California Power transmission via belts and pulleys, Knight Foundry machineshop Jet Lowe, Historic American Engineering Record

A Young Millwright Appears in California

In 1863, Samuel Newman Knight (1838 - 1913), a son of Maine and fresh from the Army Corps of Engineers in Civil War era Florida, arrived in the Mother Lode and, at the tender age of 25, set himself up in business as a'millwright'. The millwright was the renaissance man of the industrial revolution: he designed the mill building, set up the prime mover (waterwheel or stearn engine) and power transmission system, arranged the machinery for mill production and in, Samuel Knight's case, later built the machinery itself as proprietor of Knight & Co. in Sutter Creek.

Launching his new career, Knight built a ten-stamp quartz mill on Calaveras Creek. In nearby canyons, he could observe the remarkable high-pressure water blasting technique that California's gold miners were using for placer mining. This 'hydraulic mining' set the stage for the invention of the Knight Water Wheel, or impulse turbine - the most efficient prime mover ever devised, then and now: Knight's ultimate destiny was to help lay major foundation stones of today's modern hydro-electric industry.

Samuel Knight grew up near the mouth of the Presumpscot River where it flows into Casco Bay at Falmouth, Maine. When he turned 14, he left the family farm and apprenticed as a ship-joiner, possibly at the tantalizingly named Samuel Knight Shipyard (we have yet to find the family connection) on the estuary of that river. The Presumpscot - quite suggestively for a story about a young millwright -was the river most heavily utilized for mill power, per mile, in the United States.

The river's last dam then powered a triple sawmill, a combing mill and a fulling mill. The darn is gone now. In its place an awesome cataract descends into the old Knight Shipyard pool, roaring out to those who can understand its message, "Water is power!"

The ship-joiner was the shipyard artisan who did all the fine woodwork - the railings, the cabins, the ship's wheel and so forth. From the early 1800s, Maine's shipyards launched a vast fleet of seagoing vessels, establishing the United States as a pre-eminent maritime nation. Exploiting virgin pine forests that provided timber ideal for taIlship masting, the myriad ship builders of "The Pine Tree State" joined the first phase of America's industrialized manufacturing.

Thus, by 1852, when Samuel Knight was apprenticed, ship-joinery was becoming much more than a traditional handcraft. A surviving ship-joiner's shop in Bath, Maine, in all its complexity of machine tools and line-shaft belt-power systems, feels just like the Knight Foundry machine shop. Even the iron-rod tensioned roof trusses in the shop building at Bath are identical to those Knight employed at Knight Foundry. This evolving work environment of Samuel Knight's early years has an obvious bearing for anyone following his career as an inventor (your fate, gentle reader).

In 1863, Knight found the Mother Lode alive with innovation. Some of the gold seekers from Mexico, China, Cornwall, Europe and back east in the United States brought gold mining experience with them, but were confronted :with unique and massive new challenges in both placer and hard rock mining. They responded by creating improved mining technologies, especially the California stamp mill, and by making extensive use of hydraulic mining. It was a great time to be an engineer; it'was a great time to be an inventor!

Much of California's gold was mined from loosely cemented fossil gravels deposited by ancient rivers, and laid bare in more recently formed valley walls. Dams, ditches and flumes were constructed high above these exposed deposits. The water flowed from the ditches into 'penstocks' or closed pipes that dropped down, sometimes hundreds of feet, to the 'monitors' or 'giants'. These water cannons blasted away the valley walls, carrying the gravel down to sluice boxes where the gold was recovered. The force of gravity alone provided this energy, creating 43.3 pounds per square inch of water pressure for every 100 feet of vertical 'head'.

The early hydraulic miners were quite resourceful, at first fashioning high pressure piping out of redwood staves bound with wire. By the time of Samuel Knight's arrival, extensive ditch systems had been built for hydraulicking all up and down the Sierra gold fields. Now outlawed, hydraulicking had disastrous ecological impacts: eroded badlands that haven't recovered to this day, gravel choked streams and rivers which in turn generated devastating spring flash floods, and valley farmlands buried by waves of debris.

The Millwright Turns Inventor

In 1866, having assembled an impressive skill set - first as a ship-joiner in Maine, then as a machinist in Florida, and, finally as a Mother Lode millwright - Samuel Knight set out to adapt the hydraulic miner's high pressure water to power a prime mover for the hard rock miner's machinery.

The Gold Rush miners of the central Sierra had been quick to locate the source of the surface placer gold - the gold bearing quartz vein~ of the famed Mother Lode - and began drilling and blasting their way down deep to follow them. Gold quartz mining and milling required heavy, energy-hungry, machinery: mine hoists, compressors and pumps, rock crushers and stamp mills.

Knight began by experimenting with wooden 'hurdy-gurdy' wheels, as were other local millwrights. Directing a jet of water against the flat uprights of a wheel shaped like a circular saw blade, perhaps 40% of the water's kinetic energy was captured - not enough to power a large stamp mill.

In 1868, Knight made the first of a series of innovations that, a quarter century later, culminated in his pioneering hydro-electric "Dynamo Motor". He attached curved buckets to the edge of the wheel, and the efficiency doubled! He had invented the Knight Wheel.

The fundamental principle he exploited is that if the water jets into the bucket at a velocity of 100 miles per hour, and the buckets are traveling by at 50 miles per hour, the water does a Uturn in the bucket and drops out at zero miles per hour. In other words, the buckets must travel at about half the speed of the water when the wheel is doing work. In theory and in fact, most of the water's kinetic energy is thus passed on to the wheel.

This wheel with curved buckets powered by a high pressure water jet is called an "impulse turbine", or all too commonly, alas, the Pelton Wheel.

Lester Pelton's 1878 observation of a misaligned Knight Wheel inspired him to introduce his split bucket design that exhausts the water more efficiently, which he patented in 1880. Pelton was a true entrepreneur; Knight an artisan, an engineer who expected his reputation to do his marketing for him. Because Pelton succeeded so notably in promoting his style of wheel, Knight Foundry got left behind in its original condition - a silver lining for us today, if not for Mr. Knight.

The final form of the modern impulse turbine, with a radical redesign of both the double bucket and the nozzle, was developed and patented by William A. Doble in 1899. When Doble took over the Pelton firm to manufacture his own design he did not change the name to Doble Wheel, probably because of the brand name recognition of the Pelton Wheel. Thus Samuel Knight's invention is commonly known today as the Pelton Wheel. Today's modern impulse turbines, descendants of the original Knight Wheel, are 90% to 92% efficient.

The Invention Inspires a Wave of Power Canal Building

Until 1868, the prime movers for hard rock mining and milling had been traditional creekside water wheels or wood-fueled steam engines - the old style water wheels useful only during the rainy season and the steam boiler fireboxes at a large mine like the Kennedy devouring as much as one hundred cords a day of increasingly scarce and expensive firewood. News of Knight's revolutionary new prime mover spread like wildfire; the Knight Wheel spawned many imitators. Donnelly Foundry in Sutter Creek manufactured its own version of the impulse turbine in competition with Knight & Co.

In Amador County, the mines running from Jackson to Plymouth produced one-half of the gold mined from the Motherlode; for most of that short 15-mile stretch there was a mine every few hundred yards. Today, there is still impressive evidence of this intensive industrial activity hidden above Highway 49. Driving on back roads from one mining ruin to the next, you move through a continuous industrial "made landscape" of foundations, headframes, holding ponds and tailing piles. (Roadside signs marking the major mines and a driving tour map, both developed by historian Robert Richards, provide an excellent guide to these landmarks.)

All over the western mining districts, !:,he Knight Water Wheel triggered widespread investment in canals built specifically to deliver water to power the new impulse turbine. The Amador Canal and Mining Company was one of the first, completing the 60 mile long spine of the Amador Canal in 1874.

The company's canal system was supplied by a darn high on the Mokelumne River,followed the ridges for 45 miles to just above Sutter Creek, then branched south to Jackson and north another 15 miles along the ridge east of Dry Town, where it entered a two mile long penstock and was carried under pressure to Plymouth. The western lone Canal branch sent water to lone, another drop of 800 feet to power mines down below. Minor branches radiated out providing water to every major hardrock mine in Amador County. Once the canal was finished, water for power cost one-fifth the cost of the fire wood needed to generate the equivalent amount of stearn power and, having a major river for its source, ran yearround, unlike the traditional stream-side water wheels.

The Invention Spreads Everywhere

Campbell & Hall - soon to be reorganized as Knight & Co., Manufacturers of Water Wheels, Hydraulic Engines, Quartz Mills, Hoisting & Pump Works - was formed in 1872, Horace Aurelius Campbell supplying the necessary capital; David K. Hall, an experienced Pennsylvania foundryman and millwright Samuel Knight almost certainly designing the facility. The Amador Canal wasn't watered until 1874. How did Knight powered the shop for those first two years - steam power? We find no trace of a stationary stearn power plant on site.

Recently, Knight Foundry historian Ed Arata discovered an 1873 Sutter Creek Independent article reporting that Knight had set up a low head Knight Wheel just above the foundry and ran the power to Campbell & Hall by a traveling cable system. Just what we would expect of this man! Ed also located a photograph showing this wheel, which we reprint here.

Knight & Co. became the 'master millwright's ideal workshop. In one integrated , manufacturing complex, Samuel Knight brought together all the production resources needed to outfit a hard rock mining operation, with the Knight Water Wheel as his signature product. In 1875, during his first years directing affairs at Knight & Co., he brought his water wheel design to a final state of development.

His perfected Knight Wheel can be identified by its curved bucket which exhausts the water toward the center of the wheel, a slit shaped nozzle to narrowly focus the jet at the center of the bucket and to extend the period the water enters the bucket (in some cases during half the rotation of the wheel), and the wheel uniquely made as a single complex iron casting"made in one piece, not a complicated lot of pieces bolted together, to get loose and out of order" as one satisfied customer wrote to Mr. Knight.

When the Amador Canal was completed in 1874, 13 mines were operating 335 stamps in their milling facilities. In 1878, just four years later, 22 mines were operating 510 stamps, now making extensive use of high-head penstocks supplied by the new canal. It appears that the majority of Amador County's mines converted from stearn engines or water wheels to impulse turbines in a short period of time, for at least some of their power needs.

Small businesses quickly found uses for the impulse turbine. By 1878, two to six inch piping was laid in both Sutter Creek and Amador City to create a power grid prefiguring electricity. The newspaper equipment of the Amador Record, ancestral to the Amador Ledger Dispatch you are holding in your hands (or reading on the World Wide Web as may be), was powered by a Knight Wheel. Fred Werner's sausage machine ran on water power. The Amador County Steam Laundry used a Knight Wheel to power blowers and other machinery. A water powered car lift is still in place in the floor of the Amador Motors auto service shop on Main Street. We were 'wired for water'!

Knight sold small "Knight's Water Motors" to individual homes in Sutter Creek to run washing machines, sewing machines, grindstones, dumbwaiters, home machine shops and rock crushers for the "high-grading" miner - another story. A six inch Knight Water Motor is quite the wee beastie, humming along at .4000 rpm. With the appearance of early Edison electric dynamos, Knight even sold water-powered generators for home use. Who will be the first reader to find a Knight Wheel hidden in their basement? When you do, this author wants to see it!

From the 1870s, and prior to the wide spread use of electricity at the turn of the century, there was a "Lost Empire" of hydraulic power distribution wherever the terrain permitted the supplying of penstocks with power canals. Knight & Co. itself was among the very first of hundreds of industries in the American West and across the country using high-pressure direct-drive impulse turbines to power their heavy machinery. Today, it is the sole surviving remnant.

The Leap to Hydro-Electricity

Samuel Knight was a prolific industrial design engineer and inventor. He created a host of novel machines, some patented and some still in use today. As he developed seemingly unrelated applications for the Knight Wheel, he was unwittingly following a thread of innovation leading him directly to hydro-electric power generation.

For instance, he invented a water-powered hoist using two Knight Wheels mounted on the same shaft but set in opposite directions. Exact and responsive control of water wheel speed is needed to drive a mine hoist safely and efficiently. To achieve this, Knight perfected and patented an intricate hydraulic cylinder activated jet valving apparatus, somewhat analogous to modern power-steering. With Knight's system, the hoist operator could control his reels with one lever, up and down. The Superintendent of Kennedy Mine wrote, "The water power machinery with reversible wheels and adjustable nozzles, etc. built by you for the Kennedy mine, works well and is giving satisfaction, and I can willingly recommend it."

He also developed water wheel governors to keep saw mills at constant speed under varying loads and compressors at constant pressure, while significantly reducing the expense of power-canal water. Wrote John Minear of the Argonaut Mine, "It does the work very nicely and saves our company $120 per month in water."

Decades of ongoing experimentation with jet and bucket forms enabled Samuel Knight to produce significant increases in the horsepower that could be generated from the same volume and press.ure of water. This progress can be tracked in the Knight & Co. catalogues and is reflected in the wooden patterns and core boxes used to make the cast iron molds for the Knight Wheels. These surviving patterns at Knight Foundry are no doubt the handicraft of the old ship-joiner, Samuel Knight himself, as this is where the actual experimenting took place. With efficient turbines and fully developed and highly sophisticated control systems 'on the shelf', Knight was poised to make the leap to hydro-electric power generation.

Knight had already been an early adopter of electricity. One evening in 1885, he invited everyone in Sutter Creek to corne down and see the first light bulbs anyone had seen hereabouts, brightly iIluminating Knight & Co. You can still trace the remains of this old 'post and tube' direct current (DC) system in the rafters of the machine shop. Ten years later, in July of 1895, the nation's first hydro-electric plant to transmit the newly perfected alternating current (AC) began generating power at Folsom for the distant Sacramento streetcar system. (This pioneering facility survives completely intact as a California State Parks unit - well worth visiting!) A second plant went online at Niagara Falls a month later.

These power plants both employed the "reaction", or "Francis turbine", the turbine type that uses low head, low-pressure water. Originally developed in the early 1800s by Uriah Boyden, it was adapted by James Francis to run the cotton mills of Lowell, Massachusetts. The reaction turbine would be typically located at the base of a dam, where the impulse turbine is found at the base of a penstock. The "Knight Water Wheel" is thus the original form of one of the two types of turbines generating the world's hydro-electricity today.

Within seven months of Folsom going online, Knight had harnessed his impulse turbines, speed governors, and mine hoist hydraulic valving systems for AC hydroelectric generation. His 'Dynamo Motor' features a complex three stage feed-back valve and jet control mechanism, using centrifugal flying ball governors and electric solenoids, and was capable of keeping generator RPMs within one percent accuracy under varying loads and water pressures, and thus AC cycles steady.

In February, 1896, he set up his prototype AC "Dynamo Motor" in Sutter Creek for the Amador Electric Railway and Light Co. (which he helped organize and which had already gone online in March 1894, doubtless with a DC system.) Was this the world's first impulse turbine powered AC hydro-electric plant? This period of power experimentation was like the early personal computer era; local inventors - and there was a locust plague of them in the late 19th century - were trying to get in on the action, and every county seemed to have its own little electric power plant set up. Samuel Knight would certainly have been a leader of the pack; was he the leader of the pack? More digging to do.

Knight & Co. quickly became a leading designer and manufacturer of hydro-electric power facilities. The Pioneer Electric plant in Ogden, Utah (then the nation's largest), plants at White River in Oregon and Bakersfield, Alturas and New Pine Creek in California soon foIlowed the Sutter Creek prototype; completed units hauled over the hill to the railroad at lone by Knight & Co:s mule teams.

Samuel Knight independently made formative contributions to the development of today's hydro-electric industry: repurposing the hydraulic mining infrastructure for industrial power, inventing the impulse turbine, perfecting sensitively valved and hydraulically controlled jets, and employing feedback speed governors - the basic outline of the system currently generating electricity at some 125 California power plants. In 1948, the California Division of Mines' "The Mother Lode Country, Centennial Edition" summed up: "Pacific Gas and Electric Company has acknowledged its debt to the California miners and the tangential water wheel. It is not too much to say that the company owed its origin to the hydraulic miners and the Pelton wheel:'

It is important that we not ignore the many paraIlel contributions made by other engineers and more successful entrepreneurs to the development of hydro-electricity. Yet there is not another place remaining in America where we can find, under one roof, a site, not only where this continuity of development took place in one unbroken process, but alsoincredible anachronism! - where the basic high-pressure water system is still intact, ready to resume its original work.

The Canal Today

The last functioning fragment of the old Amador power canal system is still sending highpressure water to Knight Foun.dry's nine impulse turbines. The water is captured from the Mokelumne River: at the Electra Diversion Dam, passes through the Electra tunnel for 43,060 feet to Tabaud Reservoir. The two purposes of this diversion nowadays are to provide a vertical head of 1,268 feet, generating water pressure of 549 pounds per square inch for the modern impulse turbines at Electra Power House via a 3,260 foot long penstock; and to send ditch water to the Amador Water Agency for water treatment and for a number of raw water customers, including Knight Foundry.

The Amador Canal passes across the South, Middle and Main Forks of Jackson Creek to Tanner Reservoir on Ridge Road above Sutter Creek for water treatment. Some of the ditch water is diverted from Tanner Reservoir into the old continuation of the Amador Ditch and its branch lone Canal, entering an inverted siphon, which functions as the penstock, 470 feet above Knight Foundry, creating a pressure of 203.5 pounds per square inch. At the bottom, a pressure reduction valve releases water to the foundry at 140 pounds per square inch, the pressure for which the turbines still driving the machinery at Samuel Knight's old millwright's shop are designed.

On the north side of the valley, the water emerges from the end of the siphon from which it continued in the (now de-watered) Amador Ditch toward Dry town. At the bottom of the siphon, water for the old lone Canal is also released at zero pressure and flows by gravity, passing in front of the foundry in a pipe under Eureka Street, and then into the open ditch just below the Badger Street bridge.

The system provides agricultural water both above (on the siphon) and below Knight Foundry. Knight Foundry consumes no water; when the turbines are running the exhaust water rejoins the flow in the lone Canal pipe outside, with just the kinetic energy removed, and goes on to provide pristine, untreated Mokelumne River water for the organically raised cattle down on the Allen Ranch.

The ditch from Tanner, the penstock running down the hill, the pipe entering the wall at Knight Foundry and the nine Knight Wheels run by the pressurized water thus represent a complete operational unit of Samuel Knight's direct-drive-hydro prime-mover system which first challenged tHe hegemony of steam power in lumber mills, mine hoist shacks and gold ore processing mills all over the Sierra and the West and then opened the way for the clean electric power generation which fueled the early 20th century California economy. It is a largely unappreciated national treasure. Federal National Landmark recognition is based on two criteria: integrity - the historic fabric must be largely intact - and unique historic significance. Knight Foundry and its functioning power canal system emphatically meet both criteria.