The commiinicafcions to the sections are of two kinds, 

 viz., papers from individuals, and reports from Com- 

 mittees. 



As to the subject matter of the papers, nothing which Papers for 

 falls within the range of Natural Knowledge, as parti- ^^|f Sections, 

 tioned among our sections, can be considered foreign 

 to the purposes of the Association ; and even many 

 applications of Science, when viewed in reference to 

 their scientific basis, may properly find a place in our 

 proceedings. So numerous, however, are the topics herein 

 comprised, so easy the transition beyond these limits, 

 that it has been thought necessary to confine ourselves 

 within this range, lest the introduction of other matters, 

 however interesting to individual members, should lead 

 to the sacrifice of more important subjects. As to 

 the form of the communications, while it is quite true 

 that every scientific conclusion should be based upon 

 substantial evidence, every theory complete, before 

 being submitted for final adoption, it is not the less 

 desirable that even tentative conclusions and hypo- 

 thetical principles when supported by sufficient prima 

 facie evidence, and enunciated in such a manner as to 

 be clearly apprehended, should find room for discussion 

 at our sectional meetings. Considering, however, our 

 limitations of time, and the varied nature of our audience, 

 it would seem not inappropriate to suspend, mentally if 

 not materially, over the doors of our section rooms, the 

 Frenchman's dictum, that no scientific theory " can be 

 " considered complete until it is so clear that it can be 

 " explained to the first man you meet in the street." 



Among the communications to the sections, un- Special 

 doubtedly the most important as a rule, are the Reports ; ^'®P^^'^^- 

 that is to say, documents issuing from specially ap- 



