Carrying the ore

Sentences without a label are documented facts; the others are marked "probable" or "uncertain".

Digging the ore was only half the work: it had to be carried out of the mountain and then on to the furnaces and the factories. For centuries this was done on people's backs and by mule; then came the roads, the inclined planes, the ropeways, the cableways and the lifts. This page follows the ore on its journey and shows the machines that water and gravity set in motion.

On their backs inside the mine

In 1829 Falquet and Banchieri write that for internal transport children of ten to twelve are employed, who load 7, 8 and even 10 rubbi of ore onto their shoulders, about 90 kilos, and carry it to the surface by climbing very steep ramps. Only in the largest workings, those of Gattino, Biava and Mongenet, is the ore carried on people's backs as far as the haulage tunnel and then continues on trucks; in the highest workings it is carried on people's backs up a difference in height of 26-30 metres. In 1824 Despines describes the most important digging, the "Ciapej" of the Gattino, with 7 or 8 levels linked by inclined shafts: the largest is called "of the four hours". Water is removed with hand pumps about 12 feet long, worked by two men.

In the 20th century the mine is organised differently. Vertical shafts let in air and send the ore down into the hoppers; descending galleries inclined at about 45 degrees, with a winch or a rack, carry it upwards; according to Beratto a vertical shaft 114 metres deep, with the lifts, links the four lower levels. The museum's website speaks instead of the yard at 890 metres and three levels below it probable: the figures add up if level 890 is counted among the four, because below it are 860, 826 and 778.

Sources: Berattino 1988, pp. 144-145, 151, 170-171; Beratto (thesis), p. 34; Museo della Miniera website, «Piazzale Bracco Giorgio D»

By mule

Until 1832 Traversella has no modern road and the ore goes down only by mule, with a load of about 80 kilos; the mule tracks are steep and full of hairpin bends and part of the load is often lost. In 1824 Despines counts every day 600-700 mules and other pack animals carrying the ore from Traversella to Lessolo in about three hours, with loads of 6-12 rubbi; animals and muleteers come from Fiorano and from Lessolo. In 1829 Falquet and Banchieri calculate an average load of 9 rubbi per animal, about 83 kilos, 57,924 journeys a year, 223 mules and 56 men, one for every four mules; from Lessolo to the works the ore continues on 60 carts of 50 rubbi drawn by one mule.

Before 1832 the main mule track went through Drusacco, Vico and Brosso and down to Calea; the branch for Ivrea and the lower Aosta Valley was the mule track "della Costa", which went down from Brosso "in steep hairpin bends" to Calea. Transport was also a checkpoint: the edicts of 1779 forbid loading at night or without a delivery note, and the regulations of 1827 oblige drivers and carriers to stop for the weighing, with a tolerance of five pounds.

Sources: Costa, Garabello 2022, slides 19, 22, 31; Berattino 1988, pp. 158, 173, 255, 258

The roads

In 1749 the Municipality of Traversella builds a large wooden bridge over the Bersella, in the area "delle Folle". The "Gastaldetti" carriage road from Traversella to Strambinello, proposed by Gattino in 1806, is built by the contractor Carlo Preverino by 1832, with a toll of 0.50 lire per quintal for thirty years: transport costs about a fifth less. To build it Preverino uses the gravel of the "giavinere", against the wishes of the people who lived on it. The French road from Lessolo to Vico, 6 kilometres long with a gradient of about 7%, soon falls into disuse; in 1880 work begins on the carriage road from Alice Superiore to Lessolo, and in 1883 the ore carts stop.

At Brosso in 1862, according to Zampari, carrying a tonne of pyrite from the mine to Ivrea costs L. 7.50, more than digging it; a cart road as far as Caglia would bring that cost down to L. 3.50.

Sources: Berattino 1988, pp. 240-241, 259-263; Zampari 1862, pp. 2-3

Inclined planes and ropeways at Brosso

At the end of the 19th century, Chiappino writes, the underground works at Brosso move from empirical techniques to rational solutions, with inclined planes and ropeways probable. On the 1924 plan of the workings, reproduced in her thesis, the winches and wheels of the inclined plane appear with the note "the full one pulls up the empty one"; the inclined plane goes down from Bore to a large building at Valcava at 362.20 metres, and Decauville narrow-gauge lines run along the valley.

In the Salvere underground workings Chiappino measured an inclined plane 20 metres long at 23 degrees and a ramp of 43 metres at 35 degrees, next to a walkway with wooden steps of about 55 metres at 25 degrees; the haulage tunnel, more than 300 metres long, still has its original rails. In 1908 the miners ask for a wage of L. 4.25 a day for the loaders of the ropeway and of L. 3.50 for the loaders of the inclined planes. A website of enthusiasts writes that the oldest rails were of wood, because iron was eaten away by the acidity uncertain.

Sources: Chiappino 2010, p. 26; Chiappino 1996, pp. 56, 64-65, 69, 71, fig. 10.1; Vescovo 2002, p. 73; mineralidelpiemonte.com, «Miniere di Brosso»

The cableways

In 1907, Chiappino writes, a cableway 3,500 metres long begins to carry the pyrite concentrate from Valcava to the railway station of Montalto Dora probable. A map of the Sclopis concessions in her thesis draws from Valcava a straight line with the word "Funicolare", ropeway, which crosses the Assa and the Dora and reaches the railway near Montaldo Dora, at 247 metres. The thesis does not say where the map comes from: if it were a plate from the 1900 monograph by Sclopis and Bonacossa, a ropeway towards Montalto would already have existed before 1907 uncertain.

Traversella too has its cableway to Montalto Dora: in 1938 according to Costa, in 1939 according to Berattino uncertain. In the area of the Bracco Giorgio yard there remain the remains of the ropeway to Montalto probable. What the cars were like and what the exact route of the two lines was, the sources read do not say.

Sources: Chiappino 2010, p. 26; Chiappino 1996, fig. 6.1, p. 48; Costa et al. 2019, p. 10; Berattino 1988, p. 263; Museo della Miniera website, «Piazzale Bracco Giorgio D»

The water that drives the machines

Along the Assa Vescovo describes water-powered stamps that are all alike: three rods of about 3.5 metres, each with a pestle over a stone mortar, lifted by the cams of a drive shaft of 3-3.5 metres turned by water probable. At Traversella the land register of 1717 records a building of "fucina e pista", forge and stamp mill, served by a mill race, and a map of 1921 shows on the right bank of the Bersella a fulling mill, a smith's workshop and a mill served by a mill race. In 1860 Sella's machines too are driven by a water wheel. In the 20th century the water of the Bersella turns the turbine of FIAT's hydroelectric power station, with transformers from 30,000 to 500 volts probable.

The cam turns the rotary motion of the shaft into reciprocating motion: as it turns it lifts the rod, then lets it fall back by its own weight. It is the same principle as the trip-hammer, which uses the energy of water to lift a hammer and let it fall; Napione, in 1785, speaks for Brosso of just such a hammer driven by water probable.

Sources: Vescovo 2002, pp. 26-27; Berattino 1988, pp. 275, 277, fig. 34; Burci 1860, p. 16; Museo della Miniera website, «Sala Edoardo Rey e delle attrezzature»

For the class

Calculations to try. The Bore inclined plane works by the rule "the full one pulls up the empty one": two trucks tied to the same cable, which runs over a wheel at the top, move in opposite directions. Write the condition for the full truck, as it goes down, to pull up the empty one without a motor: (m full − m empty)·g·sin α must exceed friction; what, then, is the brake on the wheel for? On the Salvere ramp, 43 metres long at 35 degrees, what difference in height is covered? (About 24.7 metres.) Finally: the cableway started from Valcava, where the building stands at 362.20 metres, and reached the railway near Montaldo Dora, at 247 metres; with a length of 3,500 metres, what average gradient did the line have? (About 3.3%: it is an estimate, because the two points come from different maps and we do not know the real route.)

Sources: Chiappino 1996, pp. 64-65, 69, figs 6.1 and 10.1