310 
NATURE 
[August 5, 1886 
Norfolk, in which county they remodelled most of the 
then existing decoys and constructed others. Descendants 
of the same family, having since removed to other counties, 
are some of them still celebrated for the skill with which 
they exercise the talent inherited from their forefathers. 
When “ Old George Skelton” first came into Norfolk he 
found the decoy-pipes simply grouped around the margins 
of the “Broads,” a plan which did notat all accord with his 
ideas of propriety, the great extent of water rendering it 
difficult if not impossible to have the fowl under what he 
considered proper control. He therefore selected a small 
piece of water of about two acres in extent on the banks 
of which to construct his decoy, much to the amusement 
of the local decoymen; but their derision was soon changed 
to amazement when in one week he captured 1100 teal in 
his “two-acre puddle” as they derisively termed it. The 
son of this man, also known as “Old George Skelton,” 
was equally celebrated for his skill as a decoyman, and 
left his mark upon many of the Norfolk decoys. This 
man, says Sir Ralph Gallwey, is described as a “very 
peculiar man, short of stature, web-footed like a duck, 
very strongly built, particularly kind in disposition, per- 
fectly indifferent to cold and hardship, well-informed, and 
unequalled in skill in the construction and management 
of decoys.” 
In the space at our disposal it would be impossible 
even to epitomise the full and elaborate instructions for 
erecting and working a decoy, given so clearly and pre- 
cisely that the thirty-two plans and illustrations are 
scarcely necessary for their elucidation. But with such 
assistance there should be no difficulty in erecting the 
decoy, and by following the ample instructions expe- 
rience would be gained in a season or two sufficient to 
enable almost any one to work the pipes with tolerable 
success ; but the art of decoying is only to be acquired in 
perfection by careful and continued study of the habits of 
the frequenters of the decoy pond with practice added, 
We quite agree with Sir Ralph Gallwey that there cannot 
be a more interesting adjunct to an estate than a duck 
decoy, if even it be only worked on occasions to obtain a 
supply of fowl for the table of the proprietor and as 
acceptable presents to his friends; but should he be a 
naturalist and fond of the study of birds, a peep through 
the screen of his decoy at the fowl disporting themselves 
in a state of perfect unconsciousness under his very eye 
and almost within his grasp will go far towards repaying 
him the trifling outlay the decoy will entail. Nor need 
the fact of the decoy being worked preclude the proprietor 
from the occasional use of the gun: if not persistently dis- 
turbed the fowl will speedily return, and although it is 
undoubtedly to the advantage of the decoy to be perfectly 
secluded, a very successfully worked decoy is known to 
the writer in so exposed a situation that the fowl on the 
water may be seen from a public road which passes close 
by ; it is astonishing how soon wildfowl become accus- 
tomed to sounds and sights which are not sudden or 
unexpected. : 
Sir Ralph Gallwey enumerates forty-four working 
decoys, and traces with more or less success the history 
of 149 others which have ceased to be used in England, 
and three active and nineteen disused decoys in Scotland ; 
the sister island, so far as he can ascertain, never having 
possessed a decoy. Of this large number Lincolnshire 
possessed thirty-nine, only one of which is still worked ; 
Essex thirty, three of which are still worked; Norfolk 
twenty-six, with five still worked ; and Yorkshire fourteen, 
with two only still in use. The history of these decoys as 
given by Sir Ralph Gallwey will be found replete with 
antiquarian interest as well as with abundant matter for 
the consideration of the naturalist, and his chapter on the 
Lincolnshire Fens is especially interesting. 
A short account is given of the decoys existing in 
Holland, from which country enormous numbers of fow! 
are exported annually, and which probably indicates the 
state of affairs which existed in this country in the palmy 
days of the duck decoy. A small woodcut on p. 200 
shows a form of nesting basket used by the Dutch for 
their tame decoy ducks, and which would probably prove 
an excellent contrivance for inducing wild birds to nest 
in our own shrubberies and pleasure-grounds. 
We cannot speak too highly of the plates and plans 
with which this handsome volume is illustrated, and we 
cordially recommend it to the perusal of all lovers of 
field-sports. 
COMETARY AND PLANETARY ORBITS 
Traité de la Détermination des Orbites des Cometes et 
des Planétes. Par le Chevalier Théodore d’Oppélzer, 
&c. Edition Francaise. Par Ernest Pasquier. (Paris : 
Gauthier-Villars, 1886.) 
HIS is a translation from the second edition of the 
first volume of Prof. OppOlzer’s laborious and truly 
classical work in German, on the theory and practical 
determination of the orbits of comets and planets. It has 
been made with the full assent and co-operation of the 
author, and with the assistance of Dr. Schram and others 
who greatly aided in the production of the original work. 
The volume comprises nearly 500 pages of text and 200 
pages of tables, and is an excellent specimen of typography 
throughout. Oppdlzer’s first volume is divided into two 
parts, the first termed /reparatory, the second treating of 
the determination of orbits in the various conic sections 
In the preparatory part we have chapters on the trans- 
formation of co-ordinates ; on co-ordinates in their relation 
to the time and the relation between the position of the 
celestial body in its orbit and the corresponding epoch ; 
likewise on the relation between a number of positions in 
the orbit. Thereisachapter on aberration, andan important 
one on the theoretical determination of the formulz of pre- 
cession and nutation. The second part commences with 
the treatment of parabolic orbits, of which the numerous 
cometary discoveries of the present day necessitate so 
frequent application, and there are fully-worked numerical 
examples referring to the comets 1869 III. and 188r III. 
This section is followed by a chapter, which will have 
much interest, on the determination of the orbit of a 
swarm of meteors by means of its radiant point, a problem 
which is reduced within a very small expenditure of time 
and calculation : a numerical example is worked out for 
one of Prof. Weiss’s radiants. The next section treats of 
the calculation of the orbit where no assumption is made 
with respect to the excentricity : (1) from three observa- 
tions only, as is more usually the case ; (2) where four 
observations are introduced. The well-known general 
method of Gauss was published early in the present 
