PREFACE. XI 



Students in all parts of the world, it has been considered expedient to print 

 1,500 additional copies of each for incorporation in the Miscellaneous Col- 

 lections.* 



10. Distribution of Publications. 



The distribution of the publications of the Institution is a matter which 

 i-equires much care and judicious selection, the great object being to make 

 known to the world the truths which may result from the expenditure of the 

 ,Smithson fund. For this purj^ose the Contributions are so distributed 

 as to be accessible to the greatest number of readers ; that is, to large central 

 libraries. 



The volumes of Contributions are presented on the express condition that, 

 while they are carefully preserved, they shall be accessible at all times to 

 students and others who may desire to consult them, and be returned to the 

 Institution in case the establishments to which they are presented at any time 

 cease to exist. 



These works, it must be recollected, are not of a popular character, but 

 require profound study to fully understand them ; they are, however, of im- 

 portance to the professional teacher and the popular expounder of science. 

 They contain the materials from which general treatises on special subjects 

 may be elaborated.f 



Full sets of the publications cannot be given to all who apply for them, 

 since this is impossible with the limited income of the Institution, and, indeed, 

 if care be not exercised in the distribution, so large a portion of the income 

 "will be annually expended on the production of copies for distribution of 

 what has already been published that nothing further can be done in the way 

 of new publications. It must be recollected that every addition to the list of 

 distribution not only involves the giving of the publications which have 

 already been made, but also of those which are to be made hereafter. J 



The rules governing the distribution of the Smithsonian publications are 

 appended. To enable institutions not coming within their provisos, as well as 

 individuals, to procure copies of such as may be desired, a small number is set 

 aside and sold by the Institution at a price which is intended merely to cover 

 the actual cost of their publication. 



*Prof. Baird's report for 1880. 



f Prof. Henry's report for 1876. 

 J Prof. Henry's report for 1873. 



