KiNAHAN — Report on the Clearing of Teatij Waters. 601 



age from Tigroney and Cronebane mines ; and on the right bank that 

 of Ballygahan and Ballymurtagh. Both these waters are very similar, 

 and are treated very similarly for the extraction of the copper before 

 entering the river.® They are the underground drainage of the mines, 

 rich in sulphates of copper, iron, and alumina, with smaller quantities 

 of other substances. The copper is extracted by running the water 

 over metallic iron, the copper being deposited in the metallic state, 

 and an equivalent amount of iron passes into solution, while, at the 

 same time, a quantity of gas is evolved, which where the launders are 

 underground is found to be highly inflammable ; it seems to be hydro- 

 gen, due to the decomposition of the water, and is probably mixed with 

 hydro-carbons ; the iron exists mostly in the ferrous state, and it is 

 not till the greater part of the copper has been deposited that it becomes 

 deposited as ochre." 



A sample of the Ballygahan water, taken from the launders, was 

 coloured a deep brown, and contained some ochre in suspension ; it 

 was strongly acid, with a metallic taste. Its constituents are given 

 in Table B, 'No. YI. (p. 604). These probably all occur as sulphates ; and, 

 calculating them as such, we find as follows in grains per gallon : — 



Sulphate of copper, . . 



29-5 



Sulphate of iron, 



. 710-7 



Sulphate of alumina, . 



. 712-8 



Sulphate of manganese, . 



10-7 



Sulphate of zinc, . . . 



6-0 



The most interesting constituent of this water is a small trace of 

 cobalt. Mckel, however, was not detected. 



On the opposite bank, the drainage from the Tigroney and Crone- 

 bane mines, as it enters the river, is almost identical, in general com- 

 position, with that of Ballygahan ; it, however, contains each consti- 

 tuent in less quantity. 



The river, below where this drainage enters, has in general, but 

 more markedly during warm dry weather, a somewhat turbid appear- 

 ance : this is probably due to the separation and deposition of the salts 

 of iron and alumina. 



Some distance below the Ballygahan waters another mineral stream 

 enters, on the same side, which comes down from the mines of Bally- 

 murtagh, along the Red road. This water contains very little mineral 

 salts, as compared with those just mentioned. 



8 These waters appear to have attracted some attention during the last century, 

 and are described in Eutty's Ilineral Waters of Ireland (1757), pp. 241—245 ; 

 Fhilosopliical Transactions, for 1751 to 1753, by Kenroy, Henry and Bond. 



9 This ochre consists of hydrated ferric oxide and a basic sulphate (FezSOe), 

 which separates, in the presence of cast iron, thus : 



Fe203 (S03)3 + Fe2 + 2H2O = FeoOsSOs + 2FeS04 + 2H2. 



This reaction also accounts for the hydrogen ; but some of this is also produced by 

 the couple formed by the iron and copper. 



