162 THE AMERICAN MONTHLY [July, 



named preparer, a series of whose instructive preparations was 

 selected for projection upon the screen to illustrate lectures in the 

 amphitheatre, showed comparative slides having six different 

 kinds of blood, or of wood sections, etc., ingeniously and con- 

 veniently grouped and labelled on one slide. 



Dr. Joseph Montaldo, of Turin, exhibited a large and fine col- 

 lection of slides illustrating wood-structure ; and Drs. M. and Ad. 

 Jolles, of Vienna, contributed a similarlv valuable study of food- 

 substances. 



Even more notable, though out of competition for the prizes, 

 was the collection of 10,000 preparations by a member of the jury, 

 Prof. H. Bolsius, S. J., of the theological college at Louvain. 

 These slides represented in serial sections (with also a resultant 

 monograph) a study in the anatomy of the leaches, the whole 

 being, to say the least, one of the best examples of individual 

 work in the exposition, and offering to every visitor an instructive 

 and inspiring model of good work in laboratory biology. 



Mr. Julien Deby, of England, received a gold medal in rec- 

 ognition of several series of preparations showing thoughtful and 

 able study of interesting subjects mostly connected with insect 

 and plant life. 



A notable feature of the exhibition was the free use of the 3x1 

 in. slides by continental preparers, in preference to the various so- 

 called continental sizes. If confined to professional preparers this 

 might be considered a concession to the requirements of English 

 and American buyers ; but being noticed also in the work of 

 those who prepare for their own use, it goes far toward indicating 

 that, in spite of its well-known minor disadvantages, the 3x1 

 standard was not a very undesirable selection. 



Literature. 



The invitation for an exhibition of microscopical books secured 

 only a few responses. The owners of valuable volumes are loth 

 to be separated from them for months ; and the possessors of 

 priceless rarities of this kind would seldom care to trust them in 

 a public exhibition where to be of any real use they must be 

 handled freely by the visitors. Of modern publications, only 

 the two French journals and a limited number of books and 

 pamphlets on the microscope, diatoms, botany, etc., appeared. 



One of the smallest and most unpretending of the works was 

 certainly one of the most remarkable; a little book on '•'•Sept 

 Objects Regardcs a7i Microscope " by Dr. E. Giltay, profes- 

 sor of botany in the National School of Agriculture at Wageningen, 

 Holland. The seven objects are : i, colored lines on opposite 

 sides of an object slide ; 2, a cylinder of smoked glass ; 3, starch ; 

 4, air bubbles ; 5, milk; 6, collenchyma ; 7, an Abbe diffraction 

 plate. Li describing very plainly and briefly the study of these 

 simple objects a great amount of valuable information is intro- 

 duced concerning microscopical manipulation, observation, and 



