defined in accordance with the discussion which took place at Bath and with subsequent correspondence with Professor Langley.

The British Association Committee have during the past year carefully considered the course of action taken by the American Committee and the position of British analysts now that the scope of the inquiry entered into by the former has been thus enlarged, and it has been considered advisable to publish the results of the determinations of the British analysts as soon as their work is completed. This view was communicated to Professor Langley, who in a letter received on August 7, 1891, endorses the proposed publication of the results hitherto obtained by the British Association Committee.

Owing to the very short time which has elapsed since the receipt of Professor Langley's letter and the fact that two of the British analysts have not yet forwarded their reports to the Committee, it has not yet been possible to institute a comparison of results obtained, but no time will be lost in completing the examination of the four standards at present in hand and in then preparing a report on the English results. Dr. Wedding has informed Professor Langley that the work of the German Committee is now nearly completed.

The fifth standard has not yet been prepared, some difficulty having been met with in obtaining so large a quantity of mild steel of perfectly uniform composition. It was originally proposed to make the standard of basic steel, but it was urged that greater uniformity could be obtained with crucible metal. Professor Langley states that he has made several attempts to make crucible steel sufficiently low in carbon, but finds it impossible to do so in the plumbago crucibles used in the United States. This matter is now under consideration, and it is hoped the fifth standard will be prepared shortly.

Report (provisional) of a Committee, consisting of Professors H. E. ARMSTRONG and W. R. DUNSTAN and Messrs. C. H. BOTHAMLEY and W. A. SHENSTONE (Secretary), appointed to investigate the direct formation of Haloid Compounds from pure materials.

HAVING Confirmed Wanklyn's early observation that carefully dried chlorine was practically without action on sodium, R. Cowper in 1883 (Chem. Soc. Journ.' 1883, pp. 153-155) made a number of experiments on the behaviour of dried chlorine towards other metals, and in several cases found that if dried by contact with freshly-fused calcium chloride it was without action. Thus Dutch metal was apparently still unacted on after three months' exposure in the dried gas; and zinc, in the form of foil, and magnesium wire were also unattacked. Silver and bismuth, however, were slightly acted on, and tin, antimony, and arsenic were rapidly attacked; mercury appeared to be acted on as rapidly by dried chlorine as by the moist gas.

Pringsheim has since shown that, even in the case of hydrogen and chlorine, the interaction is affected by the presence of moisture.

These, and similar observations by H. B. Dixon and others with reference to the formation of oxides from dry materials, render it desirable to more fully elucidate the conditions which determine the formation of

metallic and other chlorides and analogous compounds; and it is in this direction that the Committee are working.

Mr. Shenstone has already obtained results which are both interesting and suggestive. Chlorine prepared in the ordinary manner dried by exposure in contact with phosphoric oxide during several months was found to very readily attack mercury-a result in accordance with Cowper's observation. Nevertheless chlorine prepared in another manner was found to behave differently. With the object of testing the quality of chlorine prepared by heating platinous chloride in vacuo, tubes of such chlorine, dried by contact during several hours with phosphoric oxide, were opened under highly-purified recently-heated mercury: although the surface of the mercury in contact with the gas was very quickly tarnished, no sensible absorption occurred during many hours in daylight, but afterwards absorption took place, at first gradually, and subsequently with tolerable rapidity. Several such experiments were made with chlorine prepared from different specimens of platinous chloride, and in every case a colourless gaseous residue, not exceeding 5 per cent., was obtained, which proved to be partly soluble in water, partly in alkaline pyrogallate, and partly insoluble. (? Nitrogen.) The fact that absorption at first took place with exceeding slowness, and subsequently proceeded at a more and more rapid rate, is apparently a significant indication that the interaction of chlorine and mercury is conditioned by the presence of some third substance, and the importance of continuing the enquiry is unquestionable.

It is probable that the impurities in the gas fronı platinous chloride are derived from a basic compound. Mr. Shenstone finds that platinous chloride is to a slight extent volatile- a fact which is ordinarily overlooked, although it has been noticed by Mr. G. Matthey; hence the analysis of the substance by the ordinary method of ignition is liable to afford fallacious results.

Nearly 201. has already been expended, chiefly in the purchase of platinum and platinum apparatus. The Committee desire to be reappointed, with a grant of 30%., as the experiments are now being extended to a number of other compounds.

Provisional Report of the Committee, consisting of General FESTING, Captain ABNEY, and Professor H. E. ARMSTRONG (Secretary), on the Absorption Spectra of Pure Compounds.

THE determination of the spectra of the compounds which the Committee have fixed upon as essential has been continued, and several have been measured and classified. The work is very laborious and can only progress slowly owing to the difficulty of obtaining absolutely pure compounds, and other difficulties in the photographic method employed have also arisen. The Committee wish for reappointment to continue the investigation.

Nineteenth Report of the Committee, consisting of Professor PRESTWICH, Dr. H. W. CROSSKEY, Professors W. BOYD DAWKINS, T. MCKENNY HUGHES, and T. G. BONNEY and Messrs. C. E. DE RANCE, W. PENGELLY, J. PLANT, and R. H. TIDDEMAN, appointed for the purpose of recording the Position, Height above the Sea, Lithological Characters, Size, and Origin of the Erratic Blocks of England, Wales, and Ireland, reporting other matters of interest connected with the same, and taking measures for their preservation. (Drawn up by Dr. CROSSKEY, Secretary.)

In their last report the Committee gave some of the general results of their survey of the erratic blocks in the Midland district of England; they are unable, however, this year still further to address themselves to the task of giving a scientific arrangement to the vast number of facts that have been collected in consequence of the number of new facts which have been reported to them, and which it is necessary to record before any more systematic generalisations can be attempted.

The destruction of erratics, moreover, is going on so rapidly that already many of those described in the reports of this Committee have disappeared, and in a few years these reports will be the chief evidence of the very existence of a large series of phenomena of great importance in glacial geology.

During the past year a N.W. of England Boulder Committee has been formed, with Mr. C. E. De Rance, F.G.S., as President and Mr. Percy F. Kendall, F.G.S., as Secretary, which has already done valuable work, and promises to accomplish a survey of the erratics of the district it has undertaken to explore, so thorough, as ultimately to render a scientific arrangement of the facts possible and enable their meaning to be understood.

The Committee have to thank the N.W. of England Boulder Committee for the following communications, which contain several features of especial interest :—

(1) The group of boulders reported from Hest Bank (Lancashire) is of importance. The stones are exclusively such as might have been derived from the country at present draining into the internal angle of Morecambe Bay. Account must be taken of this fact in any attempt to explain their origin.

(2) The area occupied by drift containing Lake District erratics is extended and help given towards defining the area of their distribution on the western slopes of the Pennine chain.

(3) The remarkable sporadic grouping of large boulders is shown; for example, in the group in the river Tame when taken in connection with the records of Cheshire groups.

(4) Evidence is given of the transport and glaciation of local blocks; e.g., by the discovery of a large angular block of Ardwick limestone at Haughton Green, the nearest known outcrop of the rock being about three miles to the N.W., as well as many other angular blocks of the same limestone.

(5) The mode of transport of some erratics and their behaviour

towards the solid rocks over which they have been carried are illustrated, the account given of the Levenshulme group furnishing evidence of ice in motion.

Many noteworthy boulders and groups of boulders are also described.

LANCASHIRE.

Reported by Mr. THOMAS RANSOME.

Bolton-le-Sands.-On eastern shore of Morecambe Bay, 1 mile north of Hest Bank Railway Station; 12 ft. 6 in. x 8 ft. x 8 ft.; oblong; moved; mountain limestone; fallen from boulder clay to the sea beach.

Group.

This is a series of specimens representing all the varieties met with in an examination of the boulder clay exposed in the cliffs at Hest Bank. The determinations are by. Mr. P. F. Kendall, F.G.S.

1. Shap granite.

2. Breccia; red base with large fragments; ? Brockram.

3. Grit; greenish grey; very fine and micaceous; ? Silurian.

4. Limestone ; red base with many white encrinite stems; Carboniferous. black with lithostrotion; Carboniferous.

5.

6.

7.

9.

10.

"

pale buff with ochreous markings; Carboniferous.

pale buff with encrinite stems; Carboniferous.
earthy buff with mollusca; Carboniferous.

dark buff with dendrites; Carboniferous.

earthy red with Spirifera glabra; Carboniferous.

11. Chert with many microzoa; Carboniferous.

12.

"

black with cuboidal jointing; Carboniferous.

13. Grit; very coarse, dark red, with quartz and other pebbles the size of a pea; ? origin.

14. Sandstone, buff, speckled with brown; Carboniferous.

15.

99

dark brick red; micaceous; ? Carboniferous.

16. Grit; coarse quartzose with felspar; ? Millstone grit.

17. Breccia; andesitic with rhyolitic fragments; ? Yewdale breccia.

18. Hälleflinta'; buff greenish; Borrowdale.

19. Rhyolite; liver-coloured; flinty with few felspars and no quartz; Borrowdale.

20. ? Volcanic rock, stained with copper; ? Borrowdale.

21. Breccia; andesitic with rhyolitic fragments; Yewdale.

22. Ash; greenish to purple; Borrowdale.

23. Mica trap. Cf. those of Sedbergh and Kendal.

24. Granite; a small fragment grey, with a portion of felspar crystals containing inclusions of quartz; ? Shap.

[All these rocks appear to have been derived from the area immediately to the northward.-P. F. K.]

Reported by the Rev. C. R. BARKER, S.J., B.A.

A group of boulders from Stonyhurst College, near Whalley, Lancashire. Stonyhurst lies four miles to the west of Whalley Station, at a height of 360 feet above O.D., on the gentle south-eastern slope of Longridge Fell. The whole district is made up of Yoredale limestones and shales beautifully exposed on the banks of the river Hodder to the north-east, and of the Yoredale grits which form the Longridge Fell and all the neighbouring hills; and up to a considerable height the country is covered with a uniform coat of boulder clay, from which (except when

otherwise specified) the erratics in question have been extracted. Glacial striæ may be seen on the mountain limestone at various points some five to six miles to the north-east, near Clitheroe: these striæ, as shown by the geological survey map, point a few degrees west of south.

The two rocks which seem to be most abundantly represented among the erratics found near Stonyhurst are-first, a compact, deep, purplish red Permian marl, which is slightly exposed four miles to the north-east, near Clitheroe; secondly, a compact yellow sandstone, very persistently characterised by speckles of brown iron-oxide. I have coupled this rock with the one first mentioned because I think it likely that it, too, is Permian or Triassic. The erratics composed of these two rocks all seem to be of quite small size.

Almost as numerous as the above mentioned, and far exceeding them in size, are boulders composed of various andesitic rocks, showing a strong family likeness, perfectly fresh and hard, of a grey colour, slightly varied in different specimens by greenish and bluish tints. Many of these measure a full cubic foot or more, and show well all the characters of ice-borne boulders. Most of them are certainly identical with rocks in Borrowdale (andesites of the well-known Borrowdale series).

Next, perhaps, in frequency of occurrence come small rounded or flattened boulders of a fine-grained rose-coloured rock of syenitic aspect. Of another rock, also of syenitic aspect, but much larger grained, I procured a single boulder, the size of an infant's head, from a field-drain close to the college.

[Mr. Kendall is of opinion that both of these are varieties of the Buttermere granophyre.]

A single piece of a compact, homogeneous pink rhyolite, picked up within a mile or two of Stonyhurst.

This specimen seems to me certainly identical with a similar pink rhyolite, composing a remarkable group of large boulders a mile or two west of Dungeon Ghyll Hotel, near Grasmere, by the side of a broad path or cart-track leading up the valley to the west from the back of the hotel. Some of the boulders measured two or three cubic feet.

A few hundred feet above the college, on the slope of Longridge Fell, boulders of other than local rocks become very rare; at a height of 1,100 feet, or so, all drift has disappeared, while on the top, at a height of some 1,300 feet, I have often walked for miles, examining ground, walls, and cairn, and have never been able to find a single worn pebble or boulder-nothing but angular fragments of the local sandstone. On Fairsnape Fell, to the north, at about the same height, I have noticed the same fact.

Reported by Mr. G. J. C. BROOM, F.G.S.

Group.

St. Helen's.-New Street, on east side of borongh between Lancaster Street and Coburg Street. Largest, 2 ft. x 1 ft. 6 in. x ; Smallest, 6 in. diam. ; the majority were of small size; all water-worn. [? Rounded.P. F. K.] They occurred in boulder clay about 10-20 ft. beneath the surface in a trench 600 ft. long and 6 ft. wide. About two cartloads were found. One specimen examined was of Buttermere granophyre. [P. F. K. 6 in. x 4 in. x 2 in.; flat; egg-shaped; water-worn [? Rounded.-P. F. K.]; finely scratched and grooved upon two faces;