51 



It can hardly he less than an educational and scientific duty for us to see to 

 it that the yonng people who are graduated from our modern colleges shall have 

 at least a realizing sense of this new scientitic development, all of which has 

 grown up within the last forty years. 



The Charleston (Mo.) Earthquake. By .\. H. Purdue. 



The earthquake of October 31. 1895, is the greatest seismic disturbance that 

 has occurred in the Mississippi Valley since the noted earthquake of 1811. 

 Though nowhere intense enough to do great injury to buildings, it was perceptible 

 over an area of more than 400,000 square miles. 



A short lime after the occurrence of the earthquake the writer communicated 

 blanks to the teachers of science in seventy-five cities and towns in the States of 

 Indiana, Illinois, Missouri, Arkansas, Alabama, Mississippi, Georgia, Kentucky 

 and Tennessee, requesting information concerning the time, duration and in- 

 tensity of the shock, together with the apparent course of wave movement, and 

 subsequent phenomena. The major part of these blanks was sent to science 

 teachers of Indiana with a view to determining, if possible, Avhether the great 

 volume of gas removed in recent years has had any effect on the stability of the 

 cru.st within the gas region. It seemed not unreasonable to suppose that the 

 relief of pressure within the rocks from which gas has been removed has left them 

 in a strain, in which case the earthquake waves might produce a collapse which 

 would be indicated by their reinforced intensity. 



Of the seventy-five blanks sent out, only thirty-nine were returned, con- 

 sequently my information is not so complete as I had hoped to secure. Of the 

 thirty-nine received, however, twenty-seven are from Indiana, so that the facts 

 concerning that field are tolerably complete. 



The reports sent in substantiate what the newspapers had already indicated, 

 viz., that the epicentrum was in the vicinity of Charleston, Missouri. The per- 

 son* reporting from that place says that the force was "sufficient to break 

 several plate-glass windows, crack brick walls, and throw down brick chimneys." 

 He also reports: "'About four miles southwest of this place the ground was 

 cracked open in several places, and sand and water were forced from the fissures, 

 causing what are commonly known in this section as sandblows. For a few 

 minutes afterward water spurted from several pumps." There were at least two 



■' A. R. Boon. 



