Headden — Group of Radium-bearing Springs. 299 



collected in the bottom of the spring was found to contain an 

 abundance of beads and Indian trinkets lost by the bathers. 

 The Indians attributed great medicinal virtues to this and to 

 the other springs also. A third spring is called the Drinking 

 Spring, because the water of this spring is preferred to that 

 of any of the others for this purpose. I do not know the 

 reason for this choice, but those who are accustomed to it 

 drink it very freely. This preference is probably another 

 instance in which the general judgment has arrived at a 

 correct scientific conclusion based upon some effect which it 

 either cannot or never troubles itself to formulate. It will 

 appear later that this is the most remarkable spring in the 

 group and constitutes one of the three types to which I have 

 alluded. 



There are but three springs in the group whose waters are 

 clear ; they are the Black Spring, the Drinking Spring, and a 

 smaller one designated the Alum Spring. The other springs 

 show a pronounced milkiness. The presence of hydrogen 

 sulphide would, according to general observation, account for 

 this, especially in the case of springs having a small flow and 

 presenting a large surface to the air, such as the Bath Tub, 

 whose diameters are 19 and 27 feet respectively. Some of 

 the smaller springs, however, having a comparatively large 

 flow of water and gases — conditions tending to reduce this 

 degree of milkiness, are more turbid than the Bath Tub, and 

 suggest that the presence of hydrogen sulphide is not the 

 cause of the milkiness, which is really the case. I shall sub- 

 sequently show that it is almost wholly due to the separation of 

 baric sulphate and not to sulphur set free by the decomposition 

 of hydrogen sulphide. 



The Black Spring is clear, but it is forming little or no 

 deposit from its waters. While there is some deposit formed 

 on the shale through which the spring issues, this deposit is 

 almost pure sulphur and undoubtedly owes its origin to the 

 oxidation of the sulphide. This spring has a basin contiguous 

 to it, but the deposit forming in this is black (from which fact 

 the spring obtains its name), and consists essentially of ferrous 

 sulphide with manganous sulphide and a trace of zinc sulphide. 

 The Alum Spring is clear, but its deposits are of an entirely 

 different character from the sinter formed by the other springs. 

 The Drinking Spring is perfectly clear and sparkling, and is 

 actively depositing sinter outside of the spring. This sinter 

 is practically pure baric sulphate. 



The milkiness of the other springs is due to the separation 

 of baric sulphate in an extremely fine state of division : this 

 separation probably takes place before the waters actually 

 come to the point of their discharge. The cause of the sep- 



