FROG PRESSURE SHOE. 
261 
ledge having derived from him ; and that I claim the place only 
of a humble°follower of so distinguished a practitioner. 
It will be well recollected, that the frog bar of the shoe of Pro¬ 
fessor Coleman (by means of which he proposes to give the 
necessary degree of pressure to the frog) is welded to the toe of 
the shoe' or tip, whichever is employed, and that it, in fact, forms 
one piece. In consequence of this, except there is an uniform 
degree of pressure on all parts of the surface presented to the 
ground, one part is tending- to derange the other. Now in the shoe 
before you, you will perceive that there is no direct attachment 
between the’shoe and the frog-bar : the means by which the frog- 
bar is kept in its situation is by the use of a leather sole, to which 
the bar is rivetted ; and thus the pressure to the crust by means of 
the shoe is not at all affected by the frog-bar, nor is the pressure 
given to the frog at all interfered with by the shoe. Each part 
lias its distinct and proper action; any required degree of pressure 
can be given to the frog; the descent of the sole is not prevented; 
and any shoe (that for other reasons it might be advisable to 
adopt) will be equally well adapted here ; and, if I might presume 
to borrow an idea from the Professor, “ nature is more closely 
imitated.” 
Another disadvantage that this shoe is intended to obviate is, 
that it is not likely to be pulled off by the hind foot striking the 
frog bar; in fact, the leather will give way to such an extent in this 
case, and there being no positive attachment of the bar of the shoe, 
renders this a circumstance hardly possible to take place ; whereas 
I have found it one of very frequent occurrence in the use of a 
shoe with the frog-bar welded to it. 
In brief, it will be seen, thatthis shoe is proposed as one calcu¬ 
lated to give pressure to the frog to any required extent. In order 
vor,. vn. M m 
