152 [April 20, 
In reply to a question by Mr. McKean, as to the proof of 
disease resulting from waters containing ammonia, Dr. Morris 
said we should carefully distinguish between albuminoids, and 
albuminoid ammonia and free ammonia. No one would doubt 
the unhealthiness of water contaminated with decaying or pu- 
trescent albuminous matters. The amount, however, of albu- 
minoid and free ammonia—with the chlorides and nitrites— 
enables us to trace the previous life history of the water. As 
to such a supply being injurious to health, the record of the 
U.S. Army during operations along the Chickahominy, and 
the experiences of Dr. Livingstone and Stanley in Africa, af- 
forded the illustrations required. 
Dr. Keenig was of the opinion that the Schuylkill water was 
very much abused and was better than it looked. Its looks 
could be easily remedied by filtering. The substances in solu- 
tion in Summer and Winter only differed by a few milliyrams 
to the litre. The purifying action of the forebay was very 
great ; that there was no appreciable difference in free ammo- 
nia above and below the dam. 
Dr. Keenig believed that the danger of infection from dis- 
ease germs from fecal matter in running water was very much 
overrated. 
Dr. Horn and Mr. Burke also spoke on the subject. 
The Lves’ Stratigraphic Geological, Map was exhibited and 
explained to the Society. 
Pending nominations Nos. 1176, 1177, and 1178, and new 
nominations Nos. 1179 and 1180 were read. 
The Committee on the Library reported having held a full 
meeting and having agreed on the purchase of a number of 
Hneyclopedias, Dictionaries, etc., and works of reference, as 
ordered by the Society. 
On motion, the Society authorized the construction of 
book-cases to contain these works of reference, at a cost not to 
exceed $50. 
The Publication Committee reported having authorized the 
publication of Prof. Cope’s papers on the Hryops and on the 
Puerco Fauna, and that the same would finish the second part 
