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The Ohio Journal of Science [Vol. XIX, No. 4, 



of soil resistance to solution resistance. The use of this factor 

 was made necessary since the table of resistances and salt 

 content did not cover the whole range desired. A series of 

 resistances for sodium chloride solution, ranging from 0.5 

 grams to 2500 grams per 100,000 of water was determined on 

 the Bridge, and by using the factor 1.45 and interpolating, the 

 results given in Table II were obtained. No great degree of 

 accuracy is claimed for the results, but the measurements are 

 roughly approximate, and give some idea of the soluble salt con- 

 tent in the volcanic ash deposits. Included in the table are two 



Photograph by R. F. Griggs 



DEPOSIT OF BARE ASH ON PILLAR MOUNTAIN, KODIAK. 



Determinations of ferrous iron, acidity, soluble salt content, ammonia, nitrite 



and total nitrogen content of this ash were made. 



measurements made with the same instrument on arable soil, 

 the samples being representative of the first six inches. The 

 Katmai River wash, where finely divided, contains a much 

 higher salt content than the normal soil or the coarse deposits, 

 such as those of the Martin Creek flat. The ash from the wind 

 blown drift on Pillar Mountain contains very little soluble salt 

 content, a factor possibly entering into the non-fertility of 

 this deposit. The two samples from the Katmai Mud Flow show 

 very little variation, although a twelvemonth elapsed between 

 the collections. The very fine upper layer of ash, as collected 



