ge , se pees rd slg O to “AP. Ph ey 8s BO = B55 
accustomed to teach. <A pe h di . the Trea- 
tise of Bridge from almost every simnidar work, is the great variety of 
problems with which the work is enriched. This feature Professor O. 
has borrowed very fully, having retained (though with considerable 
‘modification) the greater part of the Questions for Practice, contain- 
tained in the original work, and having added many more. Upon 
‘this subject he makes the following remarks. ‘A great variety of 
_ problems are annexed to each chapter, the utility of which must be 
eontons to every experienced instructor. Indeed, problems hold so 
: ant a place in the estimation of the writer, that he has intro- 
“duced them i into various parts of the work, wherever the subject ap- 
towbe susceptible of deriving aid from them. Problems put 
shigeiiiinds upon his own resources; they compel him to think for 
himself; they lead him toa just understanding of the principles.dem- 
‘onstrated ; and they teach him how to reduce his knowledge to prac- 
tice. These truths are so obvious, that it is difficult to account. for 
‘the singular fact that treatises on Natural Philosophy, usually contain 
few or no problems, although they Pad so ee a sei in nase 
whe branches of pure ma thematics.” - : sa 
ie f the wecles pt Lp 
s, Magnetism, Electricity and. ote have sore their 
rtionate share of attention. To seize upon a few principles of 
“very ext jasiee. application ; to make the learner well acquainted with 
“these ; 3 and to follow them out in many of their practical bearings 5 
are dimite which the writer has evidently had constantly in view. 
Accordingly, along with these fundamental principles, the truth of 
*which is established by the best evidence of which they are respec- 
‘tively susceptible, the learner is supplied with as great an amount of 
practical information as could be brought within so narrow limits. 
For example, in the course of the work, the student will be made 
familiarly acquainted with the principles of the Steam Eoainte! the Mi- 
-€roscope and the Telescope. 
~~. The work is neatly printed, and contains scale ieee Saisiood 
diagrams in wood, which serve a very valuable purpose, especially in 
Sinces. where the student has not the advantage of extensive experi- 
- mental illustrations ; and even where he has such aid from appara- 
“tus, the diagrams prepare him to take the benefit of them much 
more fully than he would otherwise do. 
as mosis which is prefixed to each volume, using clue 
to all the principal matters cqntained in every paragraph of the 1 
