Page:Proceedings of the Royal Society of London Vol 60.djvu/478

446 at Cauterets, which he has found to contain a considerable quantity of a mixture of argon and helium. He appears to have made a rough spectroscopic examination of the gases, and has stated in his paper that some of the lines in the red end of the spectrum do not belong to the spectrum either of argon or of helium. The author, a medical man, has dealt with the matter from a purely clinical standpoint, and his paper contains no data with regard to the supposed new lines.

To obtain samples of these gases, it was necessary to make a journey to Cauterets, and to visit the wells personally. Taking advantage of the Easter holidays, we left England provided with twelve tin cylinders, each with a capacity of 2 litres, for the purpose of collecting samples of gas from as many of the wells as we could obtain admission to. The management of the baths and wells granted us permission to visit the actual sources from which the baths, &c., are supplied, and courteously gave us every assistance, placing at our disposal the services of men connected with the different establishments. We were able to obtain samples of gas from four of the springs close to the town, but, on account of the deep snow, some of the more distant “ sources ” were quite inaccessible. The “ sources ” are for the most part situated at the end of tunnels driven for some distance into the hill-side. The water rises from below into tanks beneath the floor of the tunnels, and is conducted through pipes to the baths. Circular holes, about 9 inches diameter, in the floor formed the only means of inspecting the interior of the tanks. The gas appeared to rise with the water from natural springs in the bottom of the tanks ; it was this gas that we collected for our investigation. The apparatus employed is shown in the accompanying figure. A piece of rubber tube B is fitted on to the lower tap of the cylinder A, which was then sucked full of water. The taps were then closed, and the cylinder fixed in a vertical position, the rubber tube hanging down into the tank. A second piece of rubber tube, C, was fitted on to the funnel D, which was lowered into the tank. Water was then drawn up into the rubber tube, which was immediately slipped over the nozzle of the upper tap on the tin cylinder. The taps were then opened, and the funnel brought over some point on the floor of the tank, from which gas was escaping. The gas rising into the funnel rapidly replaced the water in the cylinder which escaped back into the tank by the lower tube. In some of the wells a large quantity of gas could be collected in a short time, but in others the bubbles rose only very slowly.

Name of “source.” Temp. Time required to fill vessels. Raillere............ 39‘5° C. One tin in two hours. Des CEufs.......... 5T0 ,, Three tins in 30 minutes. Caesar............... 46’0 „ One tin in four hours. Espagnol,.......... 46'0 „ Three tins in about 15 minutes