Here one passes abruptly from the limestone to the granite, and at once notes a corresponding difference in the flora. Among the limestone rocks the pinks show as drops of blood. On the granite are none. The fields by Roquedols are white with narcissus poeticus, not a flower of that bulb is in the calcareous fields. The distance from Meyrueis to the Aigoual is just over nineteen miles, and a carriage should be taken at least as far as to Camprieu, where Bramabiau demands a visit. On the top of the Aigoual a dinner and a bed may be obtained at the Observatory. Bramabiau may also be visited from Le Vigan. The rivulet of the Bonheur, that descends from the Col de Séyrerède near the Aigoual, after flowing over granite and schist, encounters a mass of Dolomitic limestone, through which it has bored a channel for a distance of 1,200 feet. The tunnel through which it flows is in one place open to the sky through the falling in of the roof. The name Bramabiau given to this cavern traversed by a stream is onomatopœic, and signifies the bellowing of a bull, as the water in time of flood gives forth angry sounds. Nothing surprises one more than the apparent inadequacy of the means to the end attained. The Bonheur is but a small stream, yet the work it has achieved is tremendous. But it must be borne in mind that where stands Camprieu was once a lake, the water held back by the barrier of limestone, and that the accumulated force was brought to bear on the rock to effect this tunnel of drainage. Moreover, the rock itself was full of holes like a sponge, with large vaults like huge bubbles in its interior, so that it was not a solid mass through which the stream had to bore its way. It was further aided by several springs rising within the rock, all working in their several courses to effect their escape. [Illustration: BRAMABIAU] The exploration of Bramabiau was accomplished in June, 1888, by M. Martel and his guides. They attempted first to penetrate by the opening through which the Bonheur leaps into light again, but found that the gallery consisted of a series of ascents, with cascades and pools; and although by wading and with ladders they succeeded in reaching a considerable distance, they could not attain to the point where the stream begins to dive underground. On the following day these indefatigable explorers attacked the tunnel from above, where the Bonheur enters, and were able to descend to the point reached on the preceding day, and further to pursue their course till they came out where the stream issues, a distance as the crow flies of a kilometre.