PEALE.] INFLUENCES MODIFYING GEYSERS. 425 



The following are some of his observations : 



Tapiii has a strong overflow Avhen there are north and east winds, 

 and the temperature then rises from 100° to 190'°. 



Springs at Whakarewarewa are very active during southwest and 

 westerly winds. 



Te Tarata, at Eotomahana, when there is a south wind the water re- 

 cedes from the basin, and when the wind changes it relills. 



Ketetahi, on the west slope of Tongarero, is active only during west 

 winds. 



In another spring he says that the water recedes in March or April 

 to ten or fifteen feet and remains at blood heat until December, when 

 there is an overflow and the temj^erature rises to 204° F. This agrees 

 with the statement of He)-bert Meade, who says that the Great Geyser 

 at Waikite begins to rouse from a quiescent state about the 20th of 

 December, and gradually increases in vigor until February, when it cul- 

 minates and then gradually subsides, 



In Iceland the eruptions of the Great Geyser are said to be finer after 

 rain than at any other time. Data as to the atmospheric effect in Ice- 

 land is very meager. 



In our own region we know absolutely nothing as to the etfect of dif- 

 ferent seasons upon the geysers. 



It is interesting in this connection to note that the inhabitants of 

 Stromboli use the volcano as a weather-glass. A belief has prevailed 

 from very early times that the eruptions ot the vent depend upon the 

 condition of the atmosphere. Judd thinks the opinion open to grave 

 doubt, but says it is certain that more violent paroxysms occur during 

 the winter than in the summer. Lyell says it must be admitted that 

 earthquakes and volcanic eruptions in turn react ui3on the atmosphere, 

 so that disturbances of the latter are generally the consequence rather 

 than the forerunners of volcanic disturbances. Whether this is the case 

 in the ISlew Zealand geysers we cannot say, but it would appear that the 

 effect of the atmosphere upon the geysers must be greater than their 

 effect could possibly be upon the atmosphere.* 



SYMPATHETIC OK SYNCHRONOUS ACTION. 



Almost all observers of the geysers of the Yellowstone National Park 

 have been inclined to regard the action of many geysers as sympathetic. 

 This has been sui^posed to be the case in the springs and geysers of the 

 Fountain Terrace in the Lower Fire Hole Basin, and on the platform of 

 the Giant, and near the Turban in the Upper Fire Hole Basin. These 

 facts have been detailed in Chapters VII and VIII, in Part I, and we 

 there stated our opinion that the sympathy was only api:)arent, the 

 synchronous action (or in some cases want of action) being only coinci- 

 dences, ior when we observed the same springs and geysers, the con- 

 ditions were exactly the reverse of those noted by other observers. 

 Certainly, at any rate, more extended observations are necessary to 

 determine the fact as to whether the geysers situated in close conti- 

 guity are or are not in sympathy with each other. The same uncertainty 

 on the subject is noted in respect to the Iceland geysers, some observ- 

 ers thinking them entirely independent of each other, while others be- 

 lieve that they are connected. That there are subterranean connections 

 in the water sui)ply may i)ossibly be true, but that the action of one 

 geyser is dei)endent upon the action of any of the others is, in our opinion, 

 improbable in most cases. Some of the ideas presented by writers on 



* In the coal mines explosions frequently follow sudden falls in atmospheric press- 

 ure. 



