576 PROCEEDINGS OF THE AMERICAN ACADEMY. 



" The Forms of the Magnetic Diagrams for Low Fields of Cer- 

 tain very Pure Kinds of Soft Iron which at very High Excita- 

 tions show extraordinarily Large Values of I. " By B. 0. Peirce. 



" The Reactions of Earthworms to Acids." By S. H. Hurwitz. 

 Presented by E. L. Mark. 



" On the Electromagnetic and the Thermomagnetic Effects in 

 Soft Iron." By Edwin H. Hall and L. L. Campbell. 



