Aug. 25, 1870] 
of comparison fiee from the danger of systematic error. There 
is little doubt that if the telescopes and operators practise toge- 
ther, either before or after the transit, data may be obtained for 
a satisfactory solution of the problem in question. 
To attain the object of the present paper, it is not necessary to 
enter into details respecting choice of stations and plans of obser- 
vation. I have endeavoured to show that no valuable result is 
to be expected from hastily-organised and hurriedly-equipped | 
expéditions ; that every step in planning the observations 
requires careful consideration, and that in all the preparatory 
arrangements we should make haste very slowly. I make this 
presentation with the hope that the Academy will take such | 
action in the matter as may seem proper and desirable. 
GLASGOW 
AFTER having had an existence of some fifteen or sixteen 
years, during which it has done a large amount of scientific | 
and thoroughgoing practical work, this North Country Institute 
has just deviated from its usual practice of holding its meetings | 
in Newcastle-on-Tyne, and, with thé co-operation of the Scottish | 
‘Engineers and Shipbuilders’ Association, has held a very suc- | 
cessful meeting in Glasgow, the centre of the great Scottish 
coal-field, and the head-quarters of the mining and engineering 
NATURE 
industries of Scotland, and of the shipbuilding industry of the | 
United Kingdom. The meeting began on Tuesday, the gth of | 
August, and extended over four days. On the opening day the 
Lord Provost of the City of Glasgow received and formally | 
welcomed the members of the North of England Institute in | 
name of the citizens and the Institution of Engineers and Ship- 
builders ; and thereafter the chair was taken by Mr. E. F. 
Boyd, President of the North of England Institute, and the 
business of the meeting commenced. 
There were set down for reading and discussion no fewer than 
eighteen papers, the subjects treated of being all directly con- 
nected with mining and mechanical engineering. Only three 
papers Were overtaken on the first day, when it was found that | 
the time for adjournment had arrived. The afternoon was spent 
by the members in Visiting various engineering and shipbuilding | 
works, and other manufacturing establishments, which were 
freely thrown open to inspection by their respective proprietors. 
We shall here briefly indicate the nature of the papers read 
and discussed at Tuesday’s sitting of the Institute. 
1. “On the Geology of the Coal Measures of Scotland,” 
by Mr. James Geikie, district surveyor of the Geological Survey 
of Scotland. The author described, first, the calciferous sand- 
stone series, which, when typically developed, consists of two 
groups of strata, the lower-pointing to the prevalence of marine 
conditions during the deposition of the red sandstones and con- 
glomerates, and the upper showing that during its accumulation 
marine and brackish water conditions alternated with the occa- 
Sional appearance of land surfaces. Volcanoes were somewhat 
prevalent during the ‘deposition of both groups. Second: The 
‘carboniferous limestone series, consisting of a lower group indi- 
cating marine conditions and occasional old land surfaces; a 
middle group indicating frequent land surfaces, and alternate 
brackish water and marine conditions; and an upper group 
pointing ‘chiefly to lower marine conditions, with occasional 
brackish water deposits and a few old land surfaces: both 
Submarine and subaérial volcanoes very active during the depo- 
Sition of the whole series. Third: The millstone grit, deposited — 
under almost exclusively marine conditions. Fourth : The coal 
measures, showing a prevalence of brackish or freshwater con- 
‘ditions, With abundant land surfaces, and speaking also of 
occasional inroads of the'sea. 
with the coal measures or millstone grit. Fifth : Intrusive rocks 
No igneous rocks contemporary | 
of three classes, namely, intrusive sheets, referable to close of | 
‘*coal measures” group ; bosses or pipes of tuff or agglomerate, 
probably of Permian age; and dykes of dolerite of Miocene 
ages. 
Sixth : Two systems of faults of different ages ; the oldest | 
striking N.E. and S.W., and the other, a double set, striking | 
approximately E. and W. and N. and S. Mr. Geikie, in con- | 
cluding, referred to the exceeding richness of the variety shown 
by the phenomena of the Scottish carboniferous formation, and 
‘said he had no hesitation in affirming that, when the palzonto- 
logical and geological history of the carboniferous rocks of 
Scotland were worked out, there would be prepared one of the 
most important chapters in the physical history ‘of the country. 
2. **On the Magnetic Ironstone of Rosedale Abbey, Cleve- 
land,” by Mr. John Marley, M.E. This paper treated of the 
extraordinary deposit of magnetic ironstone which occurs at 
Rosedale West, and forms a very peculiar feature in the famous 
Cleveland ironstone, regarding which various papers have been 
published since 1857, when Mr. Marley first drew the attention 
of scientific men to it. The magnetic stone occurs quite isolated 
in two troughs, one of which is go feet deep, and it contains, in 
the best specimens, from 42 to 50 per cent. of metallic iron. In 
1857 its extent was unproved, but it was believed to be very 
great, but this is now known not to be the case, from the results 
of recent borings and explorings which Mr. Marley fully de- 
| tailed. The author explained the curious geological relationship 
| which the magnetic stone bears to the top bed of the lias iron- 
| stone of Cleveland, Th lie ea 
NORTH OF ENGLAND INSTITUTE OF MINING | 2OPe 1 te Rae die, ae 9 ee 
AND MECHANICAL ENGINEERS—MEETING AT | 
Icebergs 
and glacial action were, in his opinion, inno way connected with 
the induction of the magnetic state, nor yet with the formation 
ofthe troughs. The deposits are not two beds of regular strata, 
nor are they veins, as no fissures have yet been found in the 
bottom of the troughs, although they have been diligently looked 
for. Mr, Isaac Lowthian Bell supplemented Mr. Marley’s 
description by giving the results of a visit which he had paid to 
Rosedale, and stated that the magnetic ore could not be the 
result of volcanic action, as carbon was always contained in the 
ae as also water of hydration and a notable quantity ot 
carbon. 
3. ‘*On the Duty of Cornish and other Pumping Engittes,” 
by Mr. J. B. Simpson. This paper was of especial interest on 
account of the subject treated of in it having a most intimate 
connection with the economy of fuel and the duration of the 
coal supply. After describing fully a Cornish engine recently 
erected in the Newcastle district, the author entered upon an 
examination of the details of twelve different kinds of engines, 
and compared their merits with those of the Cornish engine. 
In conclusion, he said that taking those engines into consideration, 
their average duty corresponded to a consumption of 14]b. of 
coal per horse-power per hour. Were a duty of 4lb. obtained, 
the saving in these engines alone would represent 40,000 tons of 
coal per annum, or, at 3s. per ton, 6,000/, The assumed total 
horse-power of pumping-engines in the Newcastle district is 
about 10,000, and from this the amount of the possible annual 
saving may easily be calculated. In many places ‘coal may not 
be worth 35. per ton at the pit mouth, but in the majority of 
cases its value is much greater. It is too much the practice to 
regard coal at the colliery as of little or no value, and that the 
extra Tolb, or 12]b. per horse-power per hour is not worthy of 
consideration. But fuel is not the only pecuniary part of the 
question, as extra consumption of coal means additional water, 
additional repairs, additional wear and tear, and additional 
manual labour—and these in the aggregate are very serious 
items of cost. Thetime does not seem far off when, im pumping 
and other colliery ‘engines, the effective duty of 21b. ‘or 3b. of 
coal per horse-power per hour will be considered as important as 
in the engines of London water-works and ocean steam-ships. 
In the evening of Tuesday a conversazione was held in the 
Corporation Galleries. The'east and west halls were occupied 
by numerous collections ‘of objects—geological, paleontological, 
mineralogical, metallurgical, chemical, mechanical, engineering, 
mining, &c., together with a magnificent display of photographs, 
by Annan, of the Old Glasgow College, and various engineering 
works and Clyde-built ships. This exhibition was of immense 
scientific and industrial interest, and was at once the most exten- 
sive and valuable that has been held in ‘Glasgow for many years. 
Advantage was taken of this evening’s meeting to perform an 
interesting ceremony, namely, the presentation of a ‘marble bust 
to Professor W. J. Macquorn Rankine, C.E., F.R.S., ‘first 
president of the Institution of Engineers im Scotland, as a'token 
of the appreciation and esteem ‘of the members. A duplicate 
copy of the bust was also presented to the institution as a memo- 
rial of the Professor’s labours in promoting the success of the 
institution. In the Large Upper Gallery there was an ‘exceed- 
ingly interesting exhibition by means of ‘the oxy-hydrogen light, 
of sections of fossil corals, by Mr. James Thomson, F.G.S., a 
gentleman who has of late years gone most extensively and 
enthusiastically into the study of fossil ‘corals, and made it 
almost entirely his own; and so fully persuaded are palzconto- 
logists of the great value of his investigations, that Mr. Thomson 
is assisted by a grant from the British Association, at the forth- 
coming meeting of which he jis 'to present'a second report and 
exhibit his wonderful series ‘of Specimens, 
