This fact seems to indicate that the causes of the sounds, whatever they may be, are stationary at several points; and this agrees with the statement of the natives, that they are produced by mollusca, and not by fish. They came evidently and sensibly from the depth of the lake, and there was nothing in the surrounding circumstances to support the conjecture that they could be the reverberation of noises made by insects on the shore conveyed along the surface of the water; for they were loudest and most distinct at points where the nature of the land, and the intervention of the fort and its buildings, forbade the possibility of this kind of conduction. Sounds somewhat similar are heard under water at some places on the western coast of India, especially in the harbour of Bombay.[1] At Caldera, in Chili, musical cadences are stated to issue from the sea near the landing-place; they are described as rising and falling fully four notes, resembling the tones of harp strings, and mingling like those at Batticaloa, till they produce a musical discord of great delicacy and sweetness. The same interesting phenomenon has been observed at the mouth of the Pascagoula, in the State of Mississippi, and of another river called the "Bayou coq del Inde," on the northern shore of the Gulf of Mexico. The animals from which they proceed have not been identified at either of these places, and the mystery remains unsolved, whether the sounds at Batticaloa are given forth by fishes or by molluscs.