Miscellanies. 35 ! 



■ 



ished at the close of the work. The preliminary outline of gal- 

 vanism, given in the early part of the book, and preliminary and 

 occasional experiments, made in the progress of the course, with 

 a sufficient number of galvanic batteries, enable the student to un- 

 derstand the decomposing agency of this power, and the polar ar- 

 rangement of the elements, as well as of the proximate principles; 

 and, on this head, nothing more is needed, to enable him to proceed, 

 intelligently, through the history of particular bodies. In the con- 

 clusion, therefore, the interesting topic of galvanism is, as it appears 

 to me, best understood, in its more ample details and varied experi- 

 mental illustrations. Should, however, any person use this work, 

 who is of a different opinion from that of the author, either on this 

 topic, or on that of the alkalies and earths, there is nothing to hinder 

 his bringing in the whole of galvanism, before the history of particu- 

 lar bodies ; and it will be equally optional with him, to study the al- 

 kalies and earths, either before or with the metals. When an entire 

 work is in our hands, if our views do not correspond with those of 

 the author, we can, with little inconvenience, dispose of its parts, in 

 the order which we may prefer. 



For my own convenience in teaching, and for that of my pupils 

 in learning and in reciting, the matter of the Elements is divided 

 under heads, distinguished by numerals, and under paragraphs, with 

 letters prefixed ; and capitals and italics are employed, to give prom- 

 inence to the more important parts. In general, these parts are so 

 constructed and arranged, that the reader may pass on, through the 

 portions in capitals and in italics, and leave those in small roman, with- 

 out breaking the sense ; and thus a rapid review is easily taken, with 

 the least expense of time. In most of the subjects, the principal heads, 

 (usually in small capitals,) are — I. History or Discovert. II. 

 Preparation or Process. III. Properties, physical and chemi- 

 cal ; sometimes under two distinct heads. IV. Polarity or Com- 

 position ; sometimes under subordinate heads. V. Uses. VI. 

 Miscellaneous. Arabic numerals occasionally form a connexion 

 between the greater heads and the smaller J and the latter are distin- 

 guished more rarely by large letters, but generally by small. The or- 

 der and the number of divisions are, however, varied at pleasure, with 

 the subjects. The great object in view, is to present all the subjects 

 to the pupil, in the most tangible form; so divided, under proper heads 

 and characters, that the thing wanted can be easily found ; so con- 

 densed, that the facts and deductions may be included in as small a 



