November 2007

History of Mining

The evolution of shaft sinking systems (Part 3)

By C. Graham and V. Evans

Shaft sinking from 1800 to 1900: Cousin Jacks

During the latter part of the reign of the Tudors in England (1485–1603), Saxon technicians were brought to England to teach Cornishmen to sink shafts and mine Cornwall’s extensive tin and copper deposits. This worked so effectively that by the early 19th century Cornwall possessed some of the best contemporary European mining technology.

Beginning about 1840 and repeating in 1865, Cornish mining prosperity slumped disastrously for a number of technical and economic reasons. The discovery of rich overseas copper deposits coupled with a degree of mismanagement in the Cornish mines worsened the situation, throwing Cornish shaft sinkers and miners out of work. At the same time, the 1800s saw a great deal of British capital investment in overseas mining ventures. These British-owned mining operations recruited their skilled labour from Cornwall and by the mid-1820s, Cornish miners, or “Cousin Jacks” as they were called, were to be found all across Latin America sinking shafts and developing mines. Cornish miners were also brought in to develop and mine lead deposits in the United States, as well as in Norway and Spain.

Copper was discovered in Australia in 1848 and more Cornish miners emigrated to that area to develop the mines there. Additional mineral strikes across the Americas and Australia followed, which attracted Cornish miners. By 1850, there were an estimated 7,000 Cornish miners and dependents in the upper Mississippi region. Their skills enabled them to construct the deep shafts necessary in that region as well as run the surface "diggings." Some of the Cornish miners crossed into Canada to work at the Bruce Mine in northern Ontario, which was acquired in 1847 by the Montreal Mining Company and became the first successful copper mine in Canada. The shaft was sunk and the mine operated until the 1860s, with every shaft sinker and miner being Cornish.

The discovery of gold in South Africa in 1880 provided another area where Cornish expertise in shaft sinking and mine operation was required. In the Transvaal, prior to the Boer War, an estimated 25 per cent of the white workforce was Cornish. It can therefore be seen that most of the shafts excavated during this period were sunk using very similar equipment and probably with similar advance rates.

The underground miners of Cornwall were divided into two classes—tutmen and tributers. The tutmen did “tut” work, which consisted of specific excavation projects, let out by contract to a party offering the lowest bid. A tut party consisted of a number of men, normally divided into three gangs, each of which would work an eight hour shift, so that work proceeded around the clock. When a new mine was being opened up, tutmen were employed to sink the shaft and run the levels in preparation for working the ore body. Once the ore body was reached, it was common to shift to tribute work. The work of tribute miners was organized by the regular mine supervisors. The tutmen were, in effect, shaft sinking contractors being paid according to their contract.

The invention of the steam engine was the most important innovation of the Industrial Revolution. This invention spawned two very important inventions that much improved the efficiency of shaft sinking in the early 19th century—steam-powered hoists and steam-powered pumps—both of which were pioneered in Cornwall. The Cornish steam-powered pumps were exported all over the world.

The development of steam-powered mine hoists in the early 19th century brought about a new problem. Prior to the use of a mechanically powered hoist, hoisting speeds had been rather slow. Now, with higher speeds, it was necessary to have a device that prevented the buckets from swinging in the shaft and crashing into each other when they passed in the shaft.

This problem was solved through the introduction of either rope or fixed guides, which restricted the oscillations of the moving conveyances in the shaft. The lateral movement of the hoist rope was controlled through the use of a cross-head or rider which travelled on the guides and held the hoisting rope securely in place as the bucket travelled in the shaft.

Also, with the introduction of deeper shafts, improved hoist ropes were necessary. This problem was solved when, between 1831 and 1834, Wilhelm Albert, a German mining engineer, developed the first wire rope for mine hoisting. Wilhelm Albert’s first ropes consisted of wires twisted around a hemp rope core. These ropes did not function particularly well but were followed by developments over a 40-year period (1849–1889), when the majority of the basic forms of wire rope in use today were devised.

With the utilization of steam-powered hoisting equipment came the utilization of headframes. Structures over the top of shafts had been very rudimentary when horse whims were being utilized.

Until 1840, there were very few mechanical ventilating devices used for shaft sinking. The subject of mechanical ventilation received a considerable stimulus in 1840 when the Belgium Academy of Science offered prizes for machines that could be successfully used to ventilate mine shafts. Engineers were so successful that by 1850, mechanical ventilation was the most popular ventilation system.

Much of Central Europe is underlain by a series of strata which are heavily water-bearing and very difficult to sink shafts through. In 1883, in Germany, F.H. Poetsch developed the freezing method for shaft sinking through heavily water-bearing ground. This system was extremely popular in Germany, France, Poland, the Netherlands, and Belgiam where over 100 shafts were sunk using this method.

Although it was not necessary in Canada to utilize the freezing system for shaft sinking during this time period, there have been some shafts sunk in Canada using this method, including 15 potash shafts sunk in the late 1950s and 1960s in Saskatchewan.

In addition to the freezing method, another method was discovered for assisting the process of shaft sinking through water-bearing ground—the cementation process. The first application of the cementation process took place in 1864 when a break in the brick shaft lining, at a depth of 270 feet, occurred in one of the Rhine Preussen mine shafts. The inflow was stopped by pumping in a thin water cement mix into the area of the leak using a hand pump. Over the next 30 years, a number of attempts were made to improve this process. In 1896, Monsieur A. Françoise developed his method of drilling and injecting a water cement mixture from within the shaft perimeter. Many shafts in France, Germany, and Belgium were sunk using the cementation method.

In addition to the above innovations, the 19th century saw a number of inventions that speeded the task of drilling and blasting, and thus improved shaft sinking advance rates and the safety of both shaft sinkers and miners.

  • Hazardous ignition was overcome in 1831 with the invention of the “Miners Safety Fuse” by William Bickford.
  • Nitroglycerine was discovered by Ascanio Sobrero of Italy in 1846.
  • Alfred Nobel developed a mercury fulminate blasting cap in 1865, which led to the development of the electrical detonator in the 1880s.
  • Alfred Nobel discovered dynamite for blasting in 1866.
  • Compressed air was introduced for mining power in the 1860s displacing steam. The first compressed air plants were steam-powered, however.
  • The piston-type rock drill was developed by Charles Burleigh, an American, in 1865. These were subsequently replaced by drills developed by Rand and Ingersoll in the 1870s and 1880s.
  • In the 1890s, George Leyner of Colorado introduced hollow drill steel that permitted the flushing of cuttings with a jet of air. Unfortunately, this compounded the dust problem. Leyner modified his drills to allow the injection of water as well, wetting down the dust.

All of these inventions increased shaft sinking advance rates. Drills, however, still had to be firmly mounted on columns to support their weight and resist the recoil forces. Although the drills were large and unwieldy, they were still an improvement over hand drilling.

In his booklet entitled Metal Mining Performance in Days of Hand Boring and Gunpowder, John Higgins provides information on shaft sinking advance rates for three shafts that were sunk at the Wheal Agar Mine in Cornwall between 1856 and 1860. The size of the shafts are unknown.

  • New engine shaft: depth, 105 metres; average sinking rate, 3.18 metres per month.
  • Windstraw shaft: depth, 71.7 metres; average sinking rate, 3.77 metres per month.
  • Boundary shaft: depth, 24.5 metres; average sinking rate, 4.9 metres per month.

It was not until the early 1880s that mechanized drilling was introduced to the Nova Scotia coal mines; however, their introduction did have implications for mine operators, particularly in the area of shaft sinking. A description is given as to how two Rand No. 2 rock drills were used to sink a shaft through hard rock. The shaft was divided into two compartments, each measuring 4 feet by 4 feet. Shaft excavation was 51⁄2 by 12 feet.

The day shift was the drilling shift and consisted of a foreman, two drillers, and two helpers. The men on this shift were expected to drill all the holes, as well as hoist all the drilling equipment to surface.

The second shift was composed of two muckers and a firing boss. This shift was expected to blast the four sump holes and clean up the muck generated.

The third shift was also composed of two muckers plus the firing boss. They were expected to fire the remaining holes, clean up the rock, and leave the shaft ready for the drilling shift. Using this system, it was possible to excavate at a rate of 3 feet per day. Overall advance, including lining installation, was approximately 40 feet (12 metres) per month.

During this period of time in North America, nearly all the shafts were rectangular and timber-lined. In comparison, nearly all the shafts in Europe were circular and lined with brickwork. The brickwork was generally installed from “walling stages” or “walling cradles” as they were sometimes called. In that manner, the stage could be raised as the brickwork advanced. It is said that late in this period, a Professor Galloway adopted an improved walling cradle, which consisted of two floors 10 feet 6 inches apart, that allowed the sinkers on shaft bottom to continue operations while the wallers were working above them off the walling cradle or stage. It is probably from this invention that the term Galloway stage, a modern multi-deck suspended work platform, is named.

In most of Europe at this time, shaft advances were very little faster than those being obtained in North America. Satisfactory advance rates were considered to be 15 to 20 metres per month. In South Africa, advance rates were somewhat faster, due to the use of massive amounts of labour.

Probably the first successful mechanical shaft excavating system was introduced in 1852. The Kind–Chaudron system of shaft sinking is basically boring on a huge scale. The system was developed in Germany to enable shaft sinking through heavily water-bearing ground. Between 1852 and 1904, there were 79 shafts sunk using this method, all successfully.

The Kind–Chaudron system resembles a large rod and drop drill. Instead of ordinary drill bits, massive tools called “trepans” are employed, consisting of a heavy iron frame on the lower edge on which a number of individual cutters are set. A 15 foot trepan would weigh 25 to 30 tons. The trepan is attached to a heavy rod suspended from a walking beam operated by an engine on the surface, as in ordinary boring. The advance bore is cleared of cuttings with a bailer, similar to that used in boreholes.

The entire excavation is carried out under water, then a lining of special design is lowered into place and the shaft dewatered. The lining is composed of cast iron rings bolted together at the shaft collar and gradually lowered to the shaft bottom. The space between the lining and the shaft wall is generally filled with concrete.

The Kind–Chaudron sinking system became obsolete in the early 1900s with the development of grouting and freezing systems, which were considered to be better ways of sinking through heavily water-bearing ground.

As can be seen from the table, the period from 1800 to 1900 was a period of huge improvements in shaft sinking techniques. Sinking rates increased fourfold over the previous period.


References

Brown, E.O.F. (1927). Vertical Shaft Sinking. London: Ernest Benn Ltd.

Davies, H. (1904). Coal mining. A Reader for Primary Schools and Evening Continuation Classes. Welsh Educational Publishing Co. Retrieved April 2007 from www.genuki.org.

Donaldson, F. (1912). Practical Shaft Sinking. New York: McGraw–Hill Book Company.

Hanke, N. (2001). 130 Years of Shaft Construction—with more than 180,000 Meters of Shaft Sunk. Mulheim: ThyssenKrupp.

Higgins, J. (2004). Metal mining performance in days of hand boring and gunpowder. Retrieved April 2007 from http://higgsoldminestats.com/.

Poss, J.R. (1979). The legacies of Cornwall: mining systems and miners. World Mining, September, 111–113.

Young O.E. Jr. (1976). Black Powder and Hand Steel. Norman: University of Oklahoma Press.

Young, O.E. Jr. (1970). Western Mining. Norman: University of Oklahoma Press.

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