INTRODUCTION. 3 
the use of which the strength of the arm is of no essential value, and the 
propelling power originates in chemical combustion. 
Accessory to these are groups containing those articles used in the 
manufacture, testing, loading, and transportation of these missiles, and 
the machines which drive them through the air. 
In a fourth division is the apparatus of angling, which is separated 
from hooked implements with which the form of the articles would natu- 
rally place them, since they are not implements of grasping, but partake 
of the nature of traps, being in part automatic. 
The group of nets is a heterogeneous one, as has been stated above, 
consisting of two divisions, the first that of entangling-nets, belong- 
ing properly with traps, while encircling-nets are in idea instruments 
for grasping. 4 
In arranging traps a logical succession has been preserved as far as 
possible, Those traps are considered the most simple in which the 
animal is penned by its own act, without any change in the arrange-- 
inent of the trap. The pit-falls or “‘tipes” are first, followed by the mazes 
or labyrinths of greater or less complexity. Then come the traps in 
which the entrance is closed, either by the falling of a door or by the 
falling of a box-like trap, as a whole, so as to surround the animal. 
Under clutching-traps are placed those which seize the animal, as in the 
fingers, while crushing-traps are those which seize or impale it bodily. 
Adhesive preparations, such as bird-lime, close the series. 
The accessory divisions, including hunting-animals, decoys, and dis- 
guises, and the methods and appliances of pursuit, do not admit any 
thorough classification, and are arranged with reference to convenience 
of exhibition. 
SECTION C includes all methods of utilizing animals’ products. It 
might be more satisfactorily arranged with the following section, were 
it not for the inconvenience of exhibiting models and tools in the same 
cases with the manufactured products; the arrangement of the two sec- 
tious is nearly the same. 
In SEcTION D are grouped all useful substances derived from the animal 
kingdom. In order to avoid the omission of any products which are 
or may be obtained from North American animals, this enumeration has 
been made general, those not American being included in parentheses. 
This enumeration is far from complete, and is intended simply as an 
aid to future study in the same direction. 
SECTION E includes all articles illustrating the culture and protection 
of useful animals. 
