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instruments were nearly ready for trial and verification, he proposed to devote his approaching holidays to profit by the opportunity of gaining practical instruction and experience in their use; proposing at the same time to study Professor Thomson's electrometer—the only apparatus, he says, which holds out the hope of satisfying the present exigences of science, which require continuous registration—and to obtain the other meteorological instruments and compare them with the Kew standards.
The first part of the report is dated July 25, 1861; the second part November 16, 1861, and gives an account of his second visit to the Kew Observatory. It is prefaced by acknowledgements of the kindness and help he received from Messrs. Stewart and Chambers at the Observatory, from General Sabine, Mr. Gassiot, and the whole of the "directing Committee," from the British Association, and from the Eoyal Society.
He arrived in London on tho 24th of August, and finding General Sabine absent in Wales, proceeded at once to the artists, Adie, Barrow, and Gibson, who informed him that his instruments were at Kew, whither he lost no time in repairing, and where the Director arranged that the work should begin at once. Prof, de Souza took up his abode at Richmond, and went daily to the Observatory, remaining there from 9.30 A.m. to 5.30 P.m. He speaks of the great kindness, instruction, and constant assistance which he received from the Director and the whole personal staff of the Observatory, in their different degrees and functions, in the practical study of the instruments. This study consists, he says, in setting them up in tho trial house precisely as they are to be set up at Coimbra, in determining their constants, in repeatedly observing the magnetic elements with them and comparing the results with those of the Observatory, and in reducing those observations. In the course of the observations some little faults, which would otherwise have escaped notice, were discovered in the instruments; to correct these the artists were repeatedly called to Kew, or the Director conferred with them in London.
The collection of magnetic instruments consists, firstly, of the magnetographs which register continuously tho horizontal force, the vertical force, and the declination; and, secondly, of the portable instruments, viz. Barrow's circle for the absolute determination of the inclination, with the apparatus for determining the total force by Dr. Lloyd's method; and the unifilar, by Gibson, with its apparatus for the absolute determinations of the declination, and of the horizontal force by the method of vibrations and deflections.
The magnetographs aro accompanied by three telescopes, for the direct observation of the magnetic elements when requisite, and by all things necessary for beginning work as soon as they are established—utensils for photographic manipulation, a year's supply of chemical ingredients, waxed paper, spare bell-glasses, chimneys and mirrors, coloured glasses for tho photographic house, <tc. The portable instruments, which are indispensable in an observatory, being also proper for the observations of a magnetic survey, are conveniently packed in portable boxes, and accompanied by a tripod stand.
The existence of the Astronomical Observatory at Coimbra makes it possible to dispense with a transit-instrument and clocks, but a good chronometer is essential; and by tho kind aid of the Hydrographer, Admiral "Washington, to whom General Sabine wrote on the subject, Prof, de Souza received permission to purchase one of those examined at Greenwich, and guaranteed by the Astronomer Royal, at the price which would be paid for tho same by the British Admiralty.
"Besides the barometer required for the ordinary direct observations," Prof, de Souza desired an absolute standard such as is at Kew. So large a tube could neither be filled by the ordinary method, nor, of course, transported full. The course taken was therefore to learn at Kew how to perform the filling process by Mr. Welsh's method, so as to put it in practice at Coimbra. The experiment was made with two glass tubes of ordinary size, of which Prof, de Souza filled and closed one in the proposed manner, and Mr. Casella the other, with equal success.
Prof, de Souza then ordered from Mr. Casella two tubes of large dimension, very clean and the air exhausted, with the cistern and all the appurtenances of the barometer to be made with one of them. If he succeeds, according to his hopes, as he did at Kew, Coimbra, he says, will possess an absolute standard, which will be the standard for Portugal as that of Kew is for England. But he proposes not to order the cathetometer until the tube is actually filled and raised into its proper position. He then gives the list of the other meteorological instruments, all verified at Kew.
"A standard thermometer graduated in divisions of 0*2 Centigrade. It was one of the best old tubes in the possession of the Observatory, only wanting the graduation, which was skilfully performed under my sight by the young George Whipple, assistant at the Observatory.
"Two psychrometers with divisions of 0-5 Centigrade.
"A maximum registering thermometer on Professor Phillips's principle.
"A minimum registering spirit thermometer.
"A minimum registering mercurial thermometer; a recent invention of Mr. Casella, which was tried at Kew with a good result, and may be advantageously substituted for the spirit thermometer, of which the defects have long been recognized by meteorologists.
"A Herschel'e actinometer.
"A spirit thermometer for registering terrestrial radiation, with a suitable parabolic mirror. "Two rain-gauges.
"A vaporimeter with the corresponding pluviometer."
With the above, and a pluviometer and hygrometer of Eegnault, and an anemograph by Salleron belonging to the Cabinet de Physique at Coimbra (which requires to receive some modifications), Prof, de Souza considers that an equipment is provided for immediate work, contemplating eventually the addition of "apparatus for the continuous registry of barometric and thermometric variations, the cost of which will be under £120."
The continuous registry of atmospheric electricity by the photographic process must be given up for the present: Professor Thomson's electrometer, excellent in principle, leaves, however, somewhat to be desired in practice. Prof, de Souza examined the one at Kew with great attention, watching its march carefully, and afterwards having it taken to pieces; and he is of opinion, as is also Mr. Stewart, that slight modifications would obviate some of the defects to which it is liable.
Mr. Beckley has drawn a plan and elevation for the Observatory at Coimbra, which is submitted to the Council of the University: it provides both for the instruments which have been ordered, and for such as may, it is hoped, be subsequently acquired, these being a barograph and thermograph; and possibly hereafter a photo-heliograph for obtaining images of the solar spots, especially with a view to their supposed relations to magnetic phenomena. The cost of a photo-heliograph would now be about £80. In a few years many improvements will probably be mado in it, and meantime what is wanted for this particular object may be supplied by observations of the solar spots with an ordinary telescope, or by data obtained by the Astronomical Observatory as part of its own work.
Besides the excellent collection of magnetic instruments (one of the finest and most complete in existence, with scrupulously determined constants) which is thus placed in the possession of the University of Coimbra, Prof, do Souza has blank forms for the record of all the observations, and the formula) for their reduction, collected both from the instruction given to him at Kew, and from liis own careful examination of the manuscript books of the Observatory.
The magnetic instruments have arrived safely at Coimbra, and measures have been taken for the similar conveyance of the meteorological instruments.
Mr. Beckley's drawings furnish all the data for the construction of the building, which will be simplo and of small cost. An estimate, M. de Souza says, is appended; but it does not appear in the printed report.
M. de Souza further alludes to his having reported, both to the University and to the Government, his attendance at tho Meeting of the British Association at Manchester, as a member of its Committee of Mathematics and Physics, where he was enabled to enter into relations with the distinguished men assembled there from all parts, some of whom were Directors of Observatories, who promised tho accounts of their results, and would doubtless expect his. The British Association has granted a complete copy of their annual Reports from the commencement, and with these and the works previously received, the Coimbra establishment would find itself at once in possession of a good library of the best writings on the subjects of its investigations. He once more recalls all the kindness and assistance he received in England, adding that the Boyal Society granted £30 from their "Donation-fund" for the expenses of the verification of tho magnetic instruments prepared for the Coimbra Observatory, and concludes by urging the completion of the arrangements for an establishment which he trusts will prove alike honourable to his University and to his country.
Report on the Dredging of the Northumberland Coast xind Dogger Bank, drawn up by Henry T. Mennell, on behalf of the Natural History Society of Northumberland, Durham, and Newcastle-on-Tyne, and of the Tyneside Naturalists' Field Club.
The Committee to whom the grant of the Association for "Dredging on the Dogger Bank and the coasts of Northumberland and Durham" was entrusted having, at the request of tho Natural History Society of Northumberland, Durham, and Newcastle-on-Tyne, and of the Tyneside Naturalists' Field Club, courteously committed the practical carrying out of the proposed investigations to these bodies, their members contributed the large sum required in addition to tho Association grant, and I have now to report the result of our labours.
The dredging took place at the end of August; henco tho time which has since elapsed has been too limited to do full justice to the specimens obtained in many departments.
It was confined to the following localities: 1st, on a line duo cast of' Tynemouth, extending to the Dogger Bank, a distance of about 100 miles.
The dredging commenced about twenty miles from land, was resumed at
about fifty miles from land, and continued at intervals of about five miles for the remainder of the distance.
The depth of water never exceeded 40 fathoms, and ranged chiefly from 25 to 35 fathoms, the bottom being mainly composed of fino sand and ooze.
On the second cruise, the coast twenty miles off Coquet Island, and twenty to thirty miles off Berwick, was thoroughly dredged; in the latter locality the water attained a depth of 55 fathoms, being the deepest we possess off the Northumberland coast. The bottom consisted of coarse sand and gravel.
The vessel employed was a steamer.
Tho following gentlemen have, at tho request of the two Societies, prepared lists of the specimens obtained, and are responsible for tho determination of the species, viz.:—
Mollusca (except Tunicata), Mr. H. T. Mennell.
Mollusca Tunicata, Mr. Joshua Aldor.
Crustacea, ltev. Alfred Merle Norman.
Pycnogonoidca, Mr. Georgo Hodge.
Echinodcrmata, Mr. George S. Brady.
Hydrozoa, l Mr. Joshua Alder.
Foraniinifera, Mr. Henry B. Brady, F.L.S.
The results, as arrived at by these gentlomen, are summarized below.
Cephalopoda 1 Proso- OpisUio- Nudi-brnnchiata.
Gasteropoda G4 = 51 + 7 + 6
No species new to science was obtained, and but one previously unrecorded as British. This is the Cynthia //facialis of Sars, two specimens of which had been previously obtained by Mr. John Stanger on tho Northumberland coast, and noticed in the Tyneside Club Transactions under tho provisional name of Cynthia vestita (Alder). It has since been ascertained, however, that Professor Sars had taken the species on the Norwegian coast, and published it in 1858 under the name we now adopt.
Four other species were added to those recorded in Mr. Alder's excellent "Catalogue of the Mollusca of Northumberland and Durham," published in tho 'Tyneside Club Transactions,' viz. Eissoa sculpta (Forbes and Hanley), new to the east coast of Britain, Eitlima nitida (Lamarck), Eulima gracilis (Alder, MR.), and Syndosmya intermedia.
Several species hitherto considered to be of great rarity on our coast were obtained in some plenty, e.g. Trophon Barvicensis, Mangelia Trevelyana, Cliemnitzia fulvocincta, Smlaria Trevelyana, Trochvs milhgramis, Puncturella Noachina, and Lucina flexxwsa. Of the rarer species previously recorded, there wero found, but not abundantly, Mangelia teres, Natica Grcenfandica, Philine quadrata, Cylichna strigelfa, Crenella decussata, and Ne&ra cuspidata. Of the special varieties of the Dogger Bank which have hitherto only been taken on the fishing-lines, the only traco obtained was a single capsulo of Fusus Turtoni. Further efforts are therefore required to ascertain the exact habitat on our coast of tho rare larger Fusi, of Bttccinum (?) Dalei and Panopasa Norvegiea. When this ia discovered wo may expect to find associated with them many interesting Boreal species, perhaps too small to have attracted the attention of the fishermen.
Some interest attaches to the subfossil or upper tertiary shells which were dredged in very deep water twenty to thirty miles east of Berwick. Amongst these wero Astarte elliptiea and Mya truncate, var. UddevalUnsis, neither of which have been found living on our coast, and Margarita cinerea, an extinct species, which has been recently dredged under similar conditions in other localities.
The whole of the Crustacea which were obtained have not as yet been examined; but among those already determined are many of great interest. In all about 90 species were dredged. Among tho Podophthalmia, mention may be made otlnachus Dorsettensis as new to the N.E. coast of England, and of Crangon spinosus, bispinosus, and Alhnanni. The last of these, a recently distinguished species, was abundant both off the Durham and Northumberland coasts. From several specimens of Hippolyte securifrons which were obtained, Mr. Norman is enabled to correct an error in the specific character which he gave at tho last mooting of tho Association, from tho Shetland type specimen. He finds that there are four instead of three pairs of spines on the front margin of the carapace, two spines being placed together over each orbit.
Both sexes of Mysis spiritus (Norman), only previously known from three or four females taken near Hartlepool, were dredged in considerable numbers; and also an undescribed species of the same genus, which Mr. Norman thus describes:—
"Mysis didelphys (Norman, n. sp.).
"Antenna! scale lanceolate, twice as long as the eye, two-jointed, ciliated all round; the second joint very short, with a rounded apex terminating in five cilia. Telson entire, not more than two-thirds the length of the intermediate, and half the length of the external lamina; of the tail; lateral margins of telson armed with ten spines, some of which are situated quite at the base; apex with a large spine at each corner, but no central intermediate spines.
"This is a much stouter species than Mysis vulgaris, to which it is nearly allied. The an ten mil scale is less produced; and the second joint is much shorter, and terminates in fivo cilia instead of in an acutely pointed spine. The telson is likewise shorter, with fewer lateral spines, and without the two intermediate apical spines which are present in M. vulgaris. Mysis didelphys was dredged in deep water, forty miles off the coast, while the habitat of M. vulgaris appears to be invariably the brackish waters of estuaries and saltmarshes."
The curious and abnormal family of tho Diastylidea was well represented by Diastylis Rathkii, Eudora truncatula, Vaunthomsonia cristata, and three undescribed species. These are thus named and described by Mr. Norman:—
"Cuma rosea (Norman, n. sp.).
"Last five segments of tho thorax uncovered by the carapace. No abdominal legs. Carapaco unarmed above and below, rounded in front. Telson well dovoloped, as long as the basal portion of the caudal appendages, furnished with two spines on each side, and having the rounded apex closely surrounded by seven subequal spines. Colour white, mottled with rosy spots. Dredged 50-60 miles east of Tynemouth.
"Cyrianassa elegans (Norman, n. sp.).
"Only three pairs of abdominal legs, which are the appendages of tho first three segments. Telson produced, as long as tho basal joints of tho caudal