PREFACE. 



I HAVE been led to believe that a popular work on the microscope and its revelations would 

 at once be interesting and useful, and this belief has resulted in the present treatise, which 

 simply exhibits and describes some of the most rare and curious objects of the microscopic 

 world, and the modes of preparing them for observation under the microscope ; together with 

 a short account of thig instrument. 



In the preparation of this volume liberal use has been made of the discoveries of the dis- 

 tinguished Ehrenberg, and I have also drawn copiously from the writings of Grew, Adams, 

 Pritchard, Mantell, Carpenter, Quekett, Hogg, Beale, and others ; and from these the greater 

 part of the illustrations have also been obtained. Without specifying other portions of the 

 book, the chapter on crystallizations (except the remarks upon snow) is the result of my own 

 observations, and the drawings it contains are the representations of actual crystallizations, 

 seen and drawn by the artist. Besides these delineations many other original drawings and 

 cuts are scattered throughout the work. 



A knowledge of the wondrous revelations of the microscope cannot but be interesting ; yet 

 I trust that the perusal of this little volume may subserve a higher purpose than to while 

 away an idle hour : that it will enkindle in the reader a desire to use this noble instrument, and 

 by its aid to explore for himself the hidden realms of Nature. A few years ago the microscope 

 was simply regarded as a costly toy, but now its value is appreciated in almost every depart- 

 ment of physical science. The information it affords the physician in reference to the tissues 

 of the human body, the nature of diseases, and the constitution of the blood, is beyond all 

 price. 



The microscope detects the u ingredients invisible to the naked eye, whether precipitated 

 in atoms or aggregated in crystals, which adulterate our food, drink, and medicines, and reveals 

 the lurking poison in the minute crystals which its solution precipitates." 



In the department of vegetable physiology it enables the observer to study the incipient 

 forms of vegetable life, and the structure of the most delicate tissues. To the geologist and 

 zoologist it is indispensable, for without it they could not read the records of the rocks, and 

 would know comparatively nothing of that luxuriant vegetation which once abounded on the 

 globe, nor of those minute animal organisms whose remains are now entombed in the lime- 

 stone strata and ranges of the earth. 



Moreover, in the world revealed by the microscope we trace the workings of Infinite Bene- 

 volence, as visibly impressed on minute forms and organizations as in the starry vault em- 

 blazoned upon its rolling worlds. Here we learn with new force the harmony of Nature with 

 Revelation, and how true it is, " that a sparrow shall not fall to the ground without our 

 Father." 



HABTFOBD, OT., August 5, 1871. 



