
Oct. 12, 1871 | 
NATURE 
467 

until within a comparatively recent period. All the early 
chronicles abound in allusions to them—Remesal. Vasquez, 
Cogolludo, Villagutierre, Juarrez, and others. Uxmal and 
Chichen Itza, which Captain Brine speaks of as ‘‘discoveries,” 
were undoubtedly occupied places at the time Grijalva touched 
the shores of Yucatan. Copan, although then a ruin, was 
visited and minutely described by Dr. Palacios as long ago 
as 1576. Captain Brine would lead us to infer that these re- 
mains have been ‘‘ discovered” since the expedition of Del Rio 
to Palenque in 1787. 
That these Ruined Cities were built by the progenitors of the 
various families of the Tzeudal or Maya stock found in Central 
America at the time of the discovery, and who are still there, 
and that many of them were then occupied and flourishing does, 
not admit of doubt—is capable of demonstration. 
Big-eyed Wonder should be eliminated from modern specula- 
tion ! E. GEO. SQUIER 
New York, Sept. 14 

The Dinnington Boulder 
I HAVE been favoured with a letter from a geologist residing 
at Newcastle-upon-Tyne, who kindly informs me that he has in- 
spected the ‘‘fossiliferous boulder,” and pronounces it to be a 
block of carboniferous limestone. 
This gentleman, from his knowledge of the district, says, that 
this limestone (underlying the coal measures) crops out about 
seven or eight miles to the west or north west of Dinnington, 
from whence probably it came. The question asked of its direc- 
tion of travel is therefore satisfactorily answered. 
J. BroucH Pow 
Barbourne, Worcester, Sept. 21 
Mechanical Drawing 
In the opening address of the President of the Mechanical 
Section of the British Association, descriptive geometry and 
geometrical projection are both spoken of as subjects of little 
yalue to the mechanical draughtsman. 
Now, being interested in the matter, I would like to ask the 
nature of that special kind of mechanical drawing of which the 
Fresident spoke, and which leads to mensuration and geometry. 
I suppose from the address, descriptive geometry and geometrical 
projection will be dispensed with, seeing, as he says, that it is 
no loss to the mechanical draughtsman to be ignorant of the 
latter. As an illustration of that 7ea/ mechanical drawing which 
he advocates, would Prof. Jenkin be kind enough to show the 
method he would adopt in the construction of a drawing which 
would show the lines of intersection of the surfaces of a cone and 
sphere whose axes are not in the same plane? 
I can assure Prof. Jenkin that a word of advice from him will 
always be a great boon to the hardworking student. 
DRAUGHTSMAN 
Fall River, Mass., Sept. 18 
Ice-Fleas 
I sHOULD have thought that the “ ice-fleas” described by Prof. 
Frankland had been almost as familiar to Alpine travellers as 
their more offensive namesakes of the chalets. They are de- 
scribed by De Saussure (Voyages, § 2249), by Mr. Morell, 
‘€ Scientific Guide to Switzerland,” p. 275 ; by myself ‘* Alpine 
Regions,” p. 207, where references are given, chiefly to a paper 
by M. Nicolet in ‘*‘ Neue Denkschriften der Allg. Schiweiz. 
Gesellsch.” vol. y. (1841) ; and by other writers on the Alps. 
T. G. BONNEY 
St. John’s College, Cambridge 
Thermometer Observation 
ONE very hot day last summer I exposed to the sun, in the 
same position, three thermometers ; No. I was a new one mounted 
on box wood, No. 2 was similar, but very dirty from exposure to 
the weather ; No. 3 is what is known as a bath thermometer, 
with a metal scale. In the shade they all agree to about 1°, 
but in the sun No. 2 rose about 8° above No 1, and No. 3 
about the same above No. 2. Here we have a discrepancy of 
about 16°, caused no doubt by the different heat absorbing and 
radiating powers of the substances on which the thermometers 
were mounted. I think this may somewhat account for the 
various readings we see announced by different observers. 
D, J. STUART 

THE USE AND ABUSE OF TESTS 
HE gradually increasing recognition of the claims of 
Science by the Government is cause for unmingled 
satisfaction to every one who is interested in the material 
and moral progress of the country. And now that the 
Government has set its hand to the work, it seems disposed 
to let no timorous counsels or half-measures prevail. 
The readiness with which the demands of astronomers 
have been met last year and this, the really admirable 
practical instruction recently given to science teachers at 
South Kensington, are evidence of the earnestness of the 
intentions of those in authority. 
In the present attitude of the Government towards 
Science, however, everything is not yet as it should be. 
Much of the practical value of this earnestness consists in 
the manner in which details are carried out,and there is one 
department of the administration in whicha spirit of mis- 
chief appears to delight in neutralising all efforts at improve- 
ment. The recent movement to compel all candidates for 
employment under Government to submit themselves to 
an educational test is in the main a good one; but it may 
be carried to an excessive, even to a ludicrous, extent. 
Tests are in themselves valueless, unless they are so 
contrived as to test the possession by the candidate of 
those qualifications which will best fit him for the office 
he aspires to fill. 
There are at the present time vacancies in one of our 
Government scientific establishments for two junior 
assistants, and the principal of the establishment was 
desirous of appointing two young men who possessed the 
needful qualifications of neat and orderly habits, punctua- 
lity, and obliging demeanour, and a love of Science for its 
own sake. The establishment in question has, however, 
the misfortune to be under the control of the Board of 
Works ; and when the authorities of this department 
heard of the vacancies, they insisted, notwithstanding 
the remonstrances of those most interested, in announcing 
them for public competition. The consequence will 
be that the posts will, in all probability, be given to those 
who display the best acquaintance with English History 
or French, but who have not proved themselves possessed 
of a single qualification for these particular posts, This 
Procrustean system of measuring all men by the same 
standard will not answer. The inevitable result will be to 
fill all the square holes with round men, and all the round 
holes with square men. As reasonably might we require 
all the clerks in the Foreign Office to be acquainted with 
the properties of the chemical elements, or every assist- 
ant in the library of the British Museum to be able to 
name the bones in the human skeleton; for these are as 
essential to the liberal education which every gentleman 
ought to possess, as a knowledge of English History or 
French. The system pursued in the British Museum, 
which is fortunately under the control of another depart- 
ment of the administration, would satisfy all reasonable 
requirements : that the principals of all establishments 
should have the right to nominate candidates to vacancies, 
subject to a qualification-test of their general acquirements. 
It is but fair that in departments where the efficiency of 
the subordinate officials depends so much on their willing- 
ness to co-operate heartily with their superiors, and on 
the possession of qualities which no examination can 
possibly test, the principals should have some voice in the 
appointment of those who may probably succeed to the 
offices they themselves occupy. An opportunity is thus 
also given for the encouragement of young scientific aspi- 
rants, who may be known as earnest and careful workers, 
but who would otherwise stand little chance of Govern- 
ment employ. 
We make these strictures in no carping spirit, but simply 
with a desire that the good work now commenced may 
not be marred by errors of administration. The only object 
of the system of competitive examinations, and of com- 
pelling all candidates for Government posts first to submit 
