ea 
April 26, 1883] 
on comparison with the table of angles given in Miller’s 
“ Mineralogy,” rendered the identification of the more con- 
spicuous planes easy. The remaining planes were then 
easily determined from the relation which connects three 
planes lying in a zone. The forms present are : oltat}s 
ajror}, r\ too}, 7{227}, x{210}, 321}, um\4to}, ty 7223}. 
I had no intention of describing the specimen at the 
time it was shown me, and did not pay enough attention 
to the physical characters of the faces to be able to recall 
them. The specimen was for the most part remarkably 
limpid, with a pale mauve tint in its purest portions. It 
was in part penetrated by fine delicate needles of epidote, 
ado 90° of 
0 157 05 
XO 139 47 
ah 7130 73 
70 i2 20 
aid’ 120 0 
Ta 735 «39 
ir 737 é 
as is shown in the very excellent diagram attached, which 
gives a very clear and accurate idea of the specimen. A 
remarkably large crystal from the same locality has 
recently been added to the mineral collection of the 
Natural History Museum, Cromwell Road. It is of a 
much deeper mauve colour than Mr. Henson’s specimen ; 
it shows the same general forms, the planes ¢ and a are 
bright and even, but the small planes, 7, 2, 7, are some- 
what rough. These same characters are also those ob- 
served on the faces of such smaller specimens as I have 
examined. W. J. L. 
THE EVOLUTION OF THE AMERICAN 
TROTTING-HORSE} 
j= American trotting-horse is an example of a new 
breed of animals in process of formation. As yet 
it can hardly be called a definite breed in which the 
special and distinctive character is either fully developed 
in quality or satisfactorily fixed by heredity. Great pro- 
gress has, however, been made, many individual animals 
have attained great speed, and all the better ones have 
derived their trotting excellence in part, at least, through 
heredity. 
The origin of most breeds is involved in considerable 
obscurity, as to how much they are due to conscious and 
how much to unconscious selection, what motives led to 
this selection, how far the enhancement of the special 
qualities have been due to physical environment, and how 
far to education, training, nourishment, or cultivation. 
* By Wm. H. Brewer, from the American Fournal of Science. 
NATURE 
609 
The formation of this new breed is so recent, the develop- 
ment of a special quality has been so marked, there is 
such an abundant literature pertaining to its history, the 
system of sporting “records” is so carefully planned and 
comprehensively conducted, and withal has become so 
extensive, that we have the data for a reasonably accurate 
determination of the influences at work which led to this 
new breed being: made, the materials of which it is 
made, and the rate of progress of the special evolution. 
It is as an implement of gambling and sport that the 
trotter has his chief value to the biological student. 
Sporting events are published or recorded as the mere 
everyday use of animals is not, and the records of races 
give numerical data by which to measure the rate of pro- 
gress. Similar data do not exist for the study of the 
evolution of any other breed. 
Incidental to the preparation of a paper pertaining to 
this matter for farmers and breeders, I have compiled and 
collated certain data which have a scientific as well as 
economic value, the more interesting portion of which I 
condense for this paper. i 
The horse has several gaits which he uses naturally, 
that is, instinctively. And besides those which are 
natural, he has been taught several artificial ones, some 
of which have been much used, particularly in the middle 
ages. But to trot fast was not natural to horses; when 
urged to speed they never assumed it, and until within a 
century the gait was neither cultivated nor wanted by any 
class of horsemen. A breed of fast trotters, had it been 
miraculously created, would doubtless soon have perished 
in that it would have had no use, satisfied no fancy, and 
found no place in either the social or industrial world as 
it then was. 
Before the present century the chief and almost sole 
uses of the horse were as an implement of war, an instru- 
ment of sport and ceremony, an index of rank and wealth, 
and an article of luxury. 
For all these uses, as then pursued, a fast trotter was 
not suited, nor was he better adapted to the heavy coaches 
over rough roads, or the slow waggon-trains of armies. The 
horse best adapted to all these, however much he may 
have varied as to size, strength, and fleetness, was one 
whose fast gait was the gallop or run rather than the trot. 
For leisurely horseback travelling the ambling gait (or 
pacing gait as it came to be called in America) was pre- 
ferred. With increasing use of horses for draft, certain 
heavy but slow breeds were developed in the Old World, 
of which the Dutch, Clydesdale, and Norman breeds are 
examples. 
The causes which led to the cultivation of the trotting 
gait in this country, and the evolution of a breed with 
which it should be instinctively the fast gait, were various, 
and the separate value of each as a factor in the problem 
would be very differently estimated by different persons 
studying the subject from different points of view. Now 
that he is so valuable and plays such a part as a horse of 
use, it is easy to see why a breed of trotting roadsters 
should be produced to meet certain important demands of 
our modern civilisation. But this does not explain how 
the process actually began. 
Reasoning a@ priorz, the trotter, as a horse of use, should 
have originated in western Europe ; as a matter of fact, 
he not only did not begin there, but he was unpopular 
there until well developed here. Locomotives began to 
draw armies to the battle-field, the war-horse declined in 
actual as well as relative importance, the modern, light, 
steel-spring, one-horse, convenient business waggon as 
well as the modern buggy came into common use after 
trotting as a sport was established, and after the gait had 
been extensively cultivated and bred to. The trotting- 
horse is specially adapted to various modern uses, but 
these uses followed his development, rather than led it, 
although in later days this factor has been an important 
one in the rate of progress. 
