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



Table I contains the results of the analysis of a seven-foot 

 deposit of the volcanic ash in position. A mountain stream, 

 undermining the deposit, exposed the horizontal layers as a 

 cut bank, and this bank was cut into with a spade for over three 

 feet and samples taken from the exposed vertical section. The 

 analyses are the average of several closely agreeing results, 

 excepting for the determination of total nitrogen. No. 6 is 

 the average of two determinations. 



The total nitrogen was determined in the laboratory on 

 ten gram samples of the air dried ash by a modification of the 

 Kjeldahl process. The diluted contents of the digestion flasks 

 were made alkaline by ammonia free sodium hydrate solution 



TABLE I. 



Nitrogen Content of Katmai Ash from a Deposit, Seven Feet Deep, on 



Observation Mountain, About Eight Miles South of Katmai Crater. 



and made up to 200 cubic centimeters. Fifty cubic centimeter 

 portions were then compared in Nessler tubes with standard 

 ammonium chloride. Blanks, treated exactly as the ash samples, 

 were run concurrently, and the ammonia content of the blank 

 subtracted from that of the ash. 



The lower layers of the ash deposit contained large pieces 

 of pumice. These were discarded and the analysis made on 

 the finer material. The relatively large ammonia content of 

 the lower 18-inch layer may be attributed to contact with the 

 pre-eruptive surface on which it rests. The upper layers have 

 lost, presumably to the atmosphere, what little ammonia they 

 may have possessed. It may be that all of the ammonia found 

 in the ash has percolated upwards from the pre-eruptive soil, 

 but the quantity is so small that it might equally well be con- 

 sidered to have come in rainwater. The eruption was accom- 

 panied by very heavy downpours, which would wash down not 



