Fan. 25, 1883] 
NATURE 
289 
bered how enormous is the extent of its cultivation in 
their hands. It is this fact which has won it its official 
status, as though poor in quinine its quality is tolerably 
uniform, and being easily grown its supply can always be 
depended on. Prof. Fliickiger gives a figure of the plant 
as well as of Cinchona Ledgeriana—the quinine bark far 
excellence—and of Remijia pedunculata, one of the sources 
of the Cinchona cuprea which has of late years been 
poured into European markets from South America. 
MARINE SURVEYING 
A Treatise on Marine Surveying. Prepared for the 
use of younger Naval Officers, by the Rev. J. L. 
Robinson, B.A., Royal Naval College. (London: 
Murray, 1882.) 
HIS book has been written apparently with the view 
of enabling young naval officers to cram themselves 
sufficiently to pass the examination in surveying at the 
Royal Naval College, and it must be conceded displays 
considerable industry on the part of Mr. Robinson, who 
has evidently taken pains to go through the examination 
papers on surveying from their commencement, to see 
what questions are usually asked, and in what form they 
could be best answered; and has besides consulted a 
large number of works bearing on surveying, a list of 
which he gives at the commencement of his treatise ; but 
we confess we are much disappointed that with such ex- 
cellent materials, so poor a result should have been pro- 
duced, for, with the exception of the chapter on tides, 
which in its way is excellent, the work is of very little 
value, and rather reminds us of that treatise of— 
** The young lady of Buckingham 
Who wrote about geese and stuffing ’em, 
But found out one day 
She’d neglected to say 
A word in ker book about plucking ’em.” 
Mr. Robinson says in his preface “he has had no intention 
to write a handbook for the use of the practical surveyor,” 
and that “such an intention might fairly be regarded 
as an impertinence in one who has never been engaged 
in the practical work of the profession,” but that he has 
had rather “the examination room and its requirements 
before him.” But did it not strike Mr. Robinson that the 
practical surveyor selected to examine the candidates 
might ask questions upon which he has neglected to 
touch, and that consequently his treatise might fail to 
ensure success in the “examination room,” notwithstand- 
ing the valuable hints he has received from Staff-Com- 
mander Johnson and his friend of great experience as a 
first-class surveyor ? 
The first chapter consists of extracts from Admiralty 
publications, but we recommend the officers at the college 
to consult those publications for themselves, more espe- 
cially the Admiralty list of abbreviations, as the illustra- 
tions in this work give a poor representation of the 
symbols and signs used by the draughtsman and engraver. 
The second chapter, on the Construction and Use of 
Scales, and the sixth, on Instruments, are derived prin- 
cipally from Heather. Here again we prefer the original 
to the copy. 
The third chapter, on Laying off Angles, merely con- 
tains a brief description of the methods of plotting angles 
by chords with a small radius. On this we would remark 
that the real value of plotting angles by chords consists 
in their being plotted with long radii, as any practical 
draughtsman could have informed the author. 
The fourth chapter is a most elaborate analysis of the 
method of Fixing a Position by Angles, &c, Surveyors 
take sextant angles, principally, to fix their positions when 
sounding, and invariably use the station pointer for that 
purpose; this chapter therefore seems to us to be firing 
a 12-ton gun at a sparrow. 
The fifth chapter, on Charts and Chart Drawing, is 
rather a description of the method of map construction, 
and contains some mis-statements. Evidently Mr. Robin- 
son is not well acquainted with the mode of constructing 
charts at the Admiralty or by surveyors, as he states in 
one paragraph that circumpolar charts are usually con- 
structed on the gnomonic projection, whereas we are not 
acquainted with one Admiralty circumpolar chart on this 
projection. It is true a diagram is published to facilitate 
the practice of great circle sailing but no circumpolar 
chart. 
The fact is all marine surveyors project their work on the 
gnomonic projection, and as the smallest scale in use is an 
inch to a mile, it is evident that the errors of this projection 
are very slight, as the largest sheet of paper that can be 
worked at conveniently is about six feet square. When the 
original surveys arrive at the Admiralty the Hydrographer 
decides in what form they shall be engraved and published. 
If the surveys are plans of harbours, they are usually pub- 
lished on the gnomonic projection (as they were origin- 
ally drawn) ; if the survey is of a coast, or to be incor- 
porated in a coast, or general sheet, it is transferred to 
the mercatorial projection, for which the meridional parts 
of the spheroid are used. Charts of the circumpolar 
region are however published on an arbitrary projection, 
in which the parallels of latitude are drawn as concentric 
circles at equal distances from the pole. 
Chapter seven is on Base Lines. Now base lines are 
principally of use to the marine surveyor as the quickest 
method of starting his work, which, when it extends over 
a large area, almost invariably depends eventually for its 
scales on astronomical observations. 
Mr. Robinson states that it is impossible to fix the posi- 
tion exactly by means of a sextant. Here we must differ 
from him, and will give one instance to the contrary. 
When the question of the boundary between the United 
States and British North America was decided, and the 
49th parallel was fixed on, Admiral Sir George Richards 
then in command of H.M. surveying vessel Plumper, at 
Vancouver's Island, was directed to ascertain the position 
of this boundary line on the western seaboard of North 
America. This he did with a sextant, and buried a mark 
in the ground on the position of the 49th parallel as ascer- 
tained by himself. The Americans sent a party for the 
Same purpose with a zenith sector and altazimuth 
and when they had fixed the position of the 49th parallel 
by these means, the difference between the two results 
was found to be less than 100 feet! It is of course as 
well that nautical surveyors should know the various 
methods employed in obtaining accurate bases for geode- 
tical measurements, but for marine surveying the same 
nicety is not required as in measuring the arc of a me- 
ridian, and it cannot be too often impressed on the mind 
