found in the Waters of Harrow gate and Askern. 107 



In places where this substance has been allowed to collect 

 for some time, a layer of darker fibres will be found to have 

 formed, which present all the chai'acters of the fibres collected 

 from the sulphuretted mud of the running streams. From 

 this circumstance I have been led to suspect that the two are 

 but different forms of the same plant. If this white substance 

 be kept in a warm room it decomposes and gives out a sul- 

 phurous smell, which is stronger and more disagreeable tlian 

 that of sulphuretted hydrogen, A film also collects ujion the 

 surface of the water, and in this state it corresponds very 

 closely to Anglada's description oi fjlairine. In one instance 

 I observed this substance to form in a glass-stopped bottle of 

 sulphur water, from which the atmospheric air was excluded, 

 with the exception of a small globule which existed in tlie 

 neck of the bottle. It forms, however, most rapidly when ex- 

 posed to the atmosphere ; and so quickly does this process go 

 on, that the stone vessels into which the water runs over at 

 the Bath-houses, if cleaned in the morning, will be found co- 

 vered in many places by night. When exposed to the air the 

 sulphur water is constantly depositing small portions of the 

 salts which it holds in solution, ^Ahich, in places where it is 

 undisturbed, mix with the vegetable fibres and present them- 

 selves in the form of crystals mixed with the fibres. In this 

 state, when collected and dried and submitted to heat, it gives 

 out sulphurous acid gas. Some of the sulphur of this com- 

 pound may be precipitated from the water ; but from the smell 

 of the fibres in decomposing, I am inclined to think that they 

 themselves contain suljjhur, and that this is the agent which 

 determines their existence and peculiar form. 



Being at Harrowgate during the past summer, I was de- 

 sirous of confirming the existence of this substance in the sul- 

 phur water tliere. In most of the wells I found on their sides 

 deposits varying in colour and appearance. The different-co- 

 loured deposits were arranged in layers, so that on examining 

 a portion it presented several layers one above the other. The 

 principal layers are green, white and red. On examining the 

 green layers I found them to consist of simple fibres of a dark 

 green colour, with transverse bands of a darker shade, re- 

 sembling some of the species of Osc'dlatoria. The white I 

 found to consist of opake masses of a crystallized character, 

 which were probably salts deposited from the waters by eva- 

 poration and the escape of carbonic acid. The red I shall 

 have occasion to mention presently, only observing now that 

 Anglada mentions having observed (jlairiae sometimes of a 

 red colour. 



