TEMPERATURE OF THE GEYSER. 



69 



rations of temperature taken at different depths of 

 the water-column during the interval between two 

 following discharges of the Geyser. 



Depth 



below the 



surface 



in feet. 



Degrees marked by the Thermometer at 



8| A.M. 



3 p.m. 



8 p.m. 



Cent. 



Fahr. 



Cent. 



Fahr. 



Cent. 



Fahr. 





 16-5 

 32-5 

 175 

 628 



82-6 



85-8 



113 



122-7 



123-6 



180-68 



186-44 



235-4 



252-86 



254-45 



85-2 

 106-4 

 120 

 123 

 127-5 



185-36 



223-52 



248 



253-4 



261-5 



84-7 

 110 

 121-8 



126-5 



184-46 



230 



251-24 



2597 



The third of these columns of temperature 

 belongs to the observations made immediately 

 before the second of the two discharges. You 

 will observe, that, just at first, the temperature of 

 the water at the bottom of the tube is above that 

 at which water would boil at the surface, that it 

 decreases always towards the upper parts, where 

 the temperature is necessarily made lower by eva- 

 poration. Again the temperature alters but little, 

 both above and below, during the whole time, 

 though in general it rises, while in the middle 

 parts a constant and quicker increase of heat occurs, 

 and at last the boiling-point due to each height is 

 actually or very nearly reached. 



Nothing now is required to disturb the balance 

 of forces at once from top to bottom, but a gentle 

 impulse, such as a slight lessening of the pressure 



