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Ne ee et 2 Alene tt ten ee i s eed a ea ane ae aa - ee een a I ha tn ee ttm Mea the Oa in moe fest eo none nett be Khe tatnta fp Me Mailine Ne te Sin Mitty tm Nanton. tonto tl wits ee ee ee ee ee ee rey er eee - —— IY ete ir nr RE, Et va a IN aS Oattie

an va : . ~ Li len bud es Rene Ce eee eu Peed ioe smn ie } Sohsdat (5, a MEMOIRS OF THE LITERARY AND PHILOSOPHICAL SOCIETY OF MANCHESTER. ——E THIRD SERIES. POUURTE VOLUME, LONDON: H. BAILLIERE, 219 Rucent Srreez, AND 290 Broapway, New York. PARIS: J. BAILLIERE, Rue Havurerevitre. Lo7t. PRINTFD BY TAYLOR AND FRANCIS, RED LION COURT. FLEET STREET, Ren! ar Ie BTN 18S 801 003) os: -B 138 bi ational a yge0S CONTENTS. ARTICLE PAGE I.—Notes on some Superficial Deposits at Great Orme’s Head, and as to the Period of its Elevation. By R. D. Darsi- Pre Be ae Ae HEM ne oh. Soule host emahio ot ahvehoneoacewetheeen cadets I II.—On the Examination of Water for Organic Matter. By R. FONTS Sighs Goll Geel ex 0 BRA Oem Oe ac ne 27, III.—Description of a Dolerite at Gleaston, in Low Furness. By E. W. Brnnzy, Gene ap Si 3 hes see Ee 89 IV.—On some Constituents of Cotton-fibre. By Epwarp Scuunck, BDRM Te a8 pid é Ata eins Sige es sed sap dthcares ust Sie nsecbi 95 V.—On Solar Radiation. By Josernm BAXxENDELL, F.R.A.S....... 128 ViI.—Solar-Radiation Observations made at Old Trafford, Man- chester. By G..V..Vennon,:l.R.AS.,-F.M.S.r...ccc...... 139 VII.—A Comparison of Solar Radiation on the Grass and at Six Feet from the Ground. By Tuomas Mackerertu, F.R.A.S., 1 ale Gch cas Scie ead aleoiy) S 2a 8 ae Se MRI ce MU Bs Eee 143 VIII.—Solar-Radiation Observations made at Eccles, near Man- chester. By Tuomas Macxerery, F.R.A.S., F.MLS....... 144 IX.—On Solar Radiation.—Part II.. By Josern BAxEnpEtn, (OLE SEES REM Sh Ce ete ee 147 X.—On the Structure of the Woody’ Zone of an Undescribed Form of Calamite. By Professor W. C. Wituiamson, Bees ean ec eueneciard ula Mera echitn w eenisniadaunteainsckaetsees 155 XI.—Some Remarks on Crystals containing Fluid. By J. B. WANG ty BEA ircaccss wcttac pase hots ene . bawta le gugaee Mee 98,6 SM EO ee ; © LL AP Sig eo > & ae + > ieee ee pane? gihy a ae ro ee Sk ; :2eibige a veer » 9 | an : ‘ rs } mate" eT ek 8p saute ea aOR Cee ted natant Ghd. Sine t ie . ies ace oun aL batty wi eg en ia gah fatbaos ihe a eae K a Ee Sy vpestege MEMOIRS OF THE LITERARY AND PHILOSOPHICAL SOCIETY OF MANCHESTER. I. Notes on some Superficial Deposits at Great Orme’s Head, and as to the Period of its Elevation. By R. D. DarsisHireE, B.A., F.G.S. Read October 15th, 1867. Amonest the most interesting inquiries of the geology of to-day are those that aim at tracing the changes of the earth’s surface which have last preceded the general con- ditions under which our present life on it obtains. These changes, if any, are due to causes still in operation, and therefore are such as in an especial degree allow the exactest analogies, to be tested by the, so to speak, experimental results of daily and local observation. The situation of superficial formations and most of their phenomena place them within the reach of rapid survey. Sections are numerous and accessible, or easily made so. The matrix is usually readily worked, and such remains of organic or mineral character as occur are generally not very difficult of identification. If to these inherent facilities be added the increasing in- terest in such questions, the growing habit of frequent travel, and the excessive opportunity of publication of the SER. III. VOL. IV. B 2 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD present day, it is perhaps not wonderful if it is particularly in this field that, by the side of the more eminent scientific students, many less-qualified observers should offer their contributions to the better knowledge of our own country or of special districts of it. If I venture to occupy the attention of the Society with the following notes, it is because circumstances and local convenience have enabled me for some years past to make frequent visits to the Great Orme’s Head, and because I think that a certain familiarity with, and a definite study of, modern sea-beaches and sea-beds, their forms and in- habitants, and the preservation and disintegration of their peculiar remains enables me to offer some special illustra- tions of its peculiar recent history. It will be convenient to preface what I have to say by a short summary of observations already recorded. Pro- fessor Ramsay (Quart. Journ. Geol. Soc. viii., 1852, and again in ‘ Old Glaciers of Switzerland and N. Wales,’ 1860), after discussing the superficial appearances of Caernarvon- shire and Anglesey, states, as a well-ascertained fact, that previously to the Tertiary Glacial epoch the grander contours of hill and valley were nearly the same as now. Much of the land was then slowly depressed beneath the sea; and icebergs drifting from the north, and pack-ice on the shores, ground along the coasts and sea-bottoms, smoothing and striating the surfaces over which they passed in contact, and, in the course of ages, depositing clay, gravel, and boulders over wide areas that had once been land. The grooves and striations on ice-smoothed rocks still bear wit- ness to the general southward course of the ocean-currents of those icy seas. The true glacial drift Mr. Ramsay traces to a height of about 2300 feet on some of the Caernarvon- shire mountains. The land then slowly rose at least this height above the sea-level ; and during this long period, while the sea was rearranging and rewearing the deposits DEPOSITS AND ELEVATION. 3 of successive shores, a second system of land-glaciation, at the same time that it bore down clay and sand and boulders of its own making, carried down off the new land much of the older superficial drift, in its turn to be also rearranged in the, so to speak, retreating ocean. The more ancient of these epochs has been elaborately discussed by an acute observer in ‘Frost and Fire’ (1865), an instructive and interesting attempt to group and generalize glacial phenomena as a part of cosmical history. The story of Great Orme’s Head, as one of the lower elevations of the district, and of its adjacent low-level lands, falls within the latest of these, and passes beyond it into the most modern of geological periods. Lately an attempt has been made by the Rev. T. G. Bonney (Geol. Mag. iv., 1867) to trace ice-action over this hill and the neighbouring range of the Little Orme’s Head. ‘This gentleman gives his reasons for supposing that during the Glacial epoch the Head was a low island with its undulating cap of ice of no great thickness,—and, as to the Little Orme’s chain of hills, observes that its undulating outlines are strongly sug- gestive of glacial action, and says that the peculiar curves of these ridges and their inner slopes can only be explained by this cause. Mr. Binney, F.R.S., in a paper read to the Manchester Geological Society (Trans. iii. 97, 1861), notes his observa- tion, at a point below the Bath-house at Llandudno, of a piece of brown limestonezn situ, scored and polished probably by ice. In the same paper Mr. Binney identified, below a superficial series of slight depth and varying constituents, a bed of brownish-coloured till, “containing angular, rounded, and partly rounded pebbles,” appearing on both coast-lines of the Llandudno isthmus. In this bed he found fragments of Turritella terebra, and pointed out its similarity with the till of the Blackpool cliffs, described by B 2 4 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD him some years ago in a paper read to this Society (vol. x. N.S.). At a higher level on the east side of the Head he noted a blackish-brown clay, with angular fragments of limestone, traceable up to 162 feet above mid-tide, containing abun- dance of Mytilus edulis, Patella vulgaris, and Littorina hittorea shells. He traced the clay 100 feet higher up, and at a height of 400 feet he distinguished a singular deposit of fine sandy shingle of small slate and Silurian gravel, very similar to that on the beach below, mixed with large peb- bles of white quartz and chert, and resting on large angu- lar pieces of limestone. In this bed he found Mytilus, Ostrea, Patella, and Littorina. The shingle appeared at first sight to have been brought up for road-repair; “ but the rounded pebbles of quartz and chert, and the fact of having traced the shells all the way up the hill, convinced him that it was a natural deposit. The fossils were similar to the shells of the adjoining sea, and clearly proved the elevation of the Head at least 400 feet in a very modern epoch, gradually raising with it the banks of shells now found on its sides, the living shells holding their place be- tween high and low water, though the land was continually going up.” In the paper already mentioned, Mr. Bonney refers to well-marked wave-marks on the face of the exposed cliff, 200 feet above the present sea-level, and mentions the oc- currence of Patella and Littorina in the talus near Pen Trwyn, the north-east point of the Head. He notes a bed of clay in Gwydfyd hollow, between the Head and Pen y Dinas, its south-eastern hill, with Tapes (pullastra?), Mytilus, Ostrea, Patella, and Littorina, and conceives the clay both here and elsewhere to have been deposited “ after the ground had pretty nearly assumed its present confi- guration, and not to have undergone much denudation during the progress of upheaval.” After noticing certain DEPOSITS AND ELEVATION. 5 deposits which he identifies as kitchen-middens at low levels on the west side of the Head, he indicates the clay (Mr. Binney’s till) on the western cliff of the isthmus, disappear- ing under sand in which are seams of Mytilus edulis, beds of which occur at intervals along the coast-section. In conclusion Mr. Bonney considers that, ‘ after the limestone hills of the district had acquired their leading forms by upheaval and marine denudation, the whole dis- trict was depressed; the summits of the low rocky islets became covered with ice-fields, which in places descended in glaciers into the sea. At this period there were oscil- lations of level, during which the two lower beds were sub- ject to slight denudation. After the deposition of the upper bed of clay, there must have been considerable denudation from the action of the retreating sea. To this must have succeeded a period of depression, during which the mussel- beds were formed; and then the whole was gradually up- heaved above the level of the sea.” In his ‘ Excursions of a Naturalist, 1867, Mr. Garner re- fers to the existence some years ago of a great accumulation of midden or refuse-heap on the west of the Head, but im- plies that what he describes is not now to be seen. Special references to other details of these or some other observations will be made in their places in the following notes. I introduce my observations by a short description of the more ancient rocky basis of the Head. Rudely outlined, this hill may be described as a great oblong mass of mountain-limestone, lying, generally speak- ing, east and west, the strata somewhat depressed along the centre line in the same direction. On the north side the tilted strata are cut down in alternate cliffs and talus- hidden scars to the sea-level in magnificent and often almost vertical precipices. On the south side a similar but less 6 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD impressive profile is footed in the isthmus of Llandudno. The greater part of the western boundary consists chiefly of a fine inland cliff half-clothed by an enormous talus, from ‘which in turn has been cut by the present sea-wash a littoral cliff. The principal cliff shows in fine sections the eleva- tion of the strata northwards and southwards. The mid- dle of the superficial valley is occupied by a long and high ridge to the east of the old semaphore-station, consisting of a coarse brown grit. On this may be scen one or two small patches, scarcely a foot square, of mountain-limestone. This and the underlying grit are the last remnants of unmeasured though doubtless enormous denudation. The huge bays that flank the Head, eastwards towards Rhos Head, and west- wards towards Puffin’s Island and Anglesea, are themselves more obvious memorials of a similar removal of vast masses of the Lower Limestone. This, however, is the story of very ancient times. On either side of the Telegraph-hill the valley falls rapidly eastward, and uniting again forms the mine-plateau, and then runs down to the south of east by the line of the “‘ Old road ” into the east side of the isthmus, and the centre of what is now Llandudno, separating Pen y Dinas, the eastern point of the hill, from the rest of the southern ridge. North of Pen y Dimas, and likewise opening towards the east, a shorter and steeper valley debouches below Gwydfyd farm towards the Llandudno bay, ending in a cliff of talus, overhanging a limestone precipice and the modern beach. The surface of those parts of the Head which are not occupied by the gritstone hill are either separate hillocks or ridges (that is to say, islands or reefs) of mountain- limestone, each with its greater or lesser sea-side cliffs or plateaux of denuded strata. Between them and on the sides of the Head, and especially in the falling val- leys, are great grass-covered slopes of superficial clays, DEPOSITS AND ELEVATION. + more or less loaded with limestone detritus of all sizes, from blocks containing many cubic yards of stone down- wards. These detached rocks crowd the sward and steeper inclines and add much to the picturesqueness of the north face and its romantic walk. They are often sharply angu- lar, but occasionally are weathered or waterworn into rounded boulders. In the flatter hollows or the lower plains of the central depression there is under the sward a certain amount of humus of no great depth. The Head is connected with the mainland of Denbighshire by the Llandudno isthmus, widening eastward to the foot of the range of limestone hills which ends northwards in Little Orme’s Head. Southwards the isthmus, embracing two or three piles of igneous and altered Silurian formation, passes towards Conway and its easternestuary. The river Conway separates it from unaltered and altered Silurian beds and the great Trap ridge of Conway Mountain. The Conway estuary on the south-west, and the tides of the Menai Straits, the Irish Sea, and Llandudno Bay on the west, north, and east,’and rain and frost above high water- mark, are continuing in this our own day the processes which in the course of ages have shaped the outline and the profiles of the head to what we now see. Its general superficial outline may be ghued to be due to prolonged subaerial and later marine erosion, pos- sibly aided at some period of the process by the friction of land or floating ice—but in the last instance, and ever since its first emergence, to a long-continued and extremely tran- quil elevation and concurrent secular subaerial degrada- tion and deposit, under the never-ceasing alternations of wind and rain, heat and cold, and vegetation. The isthmus appears to consist of ancient sea-bottom, gradually raised, and denuded in the process by currents or tide-wash, and then augmented by beach-accumulation and blown sand, each apparently derived from the eastern bay. 8 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD The western limit of this strip of land has probably undergone considerable waste. Its beach, especially where it lies nearer the open sea, is covered with boulders of all sizes, the remains of Glacial clay, to be described in the sequel. The details of the superficial marine and subaerial beds of the Head and the isthmus are the subject of this paper. As the following notes contain the results of many ex- aminations of each point, they will be arranged at once, in the order of the presumed antiquity of the successive for- mations, under the following heads :— I. Marine formations and old land. A. Sea-bottom. B. Sea-beach and beach-marks. 6. © Pholas ”’-burrows. C. Clay and “sunk-forest ” bed. Il. Subaerial deposits. Detritus in clay and earth slopes (imcluding traces of occupation by animals or men). III. Refuse-heaps and other relics of recent human occupation. I. Marine Formations.—A. Sea-bottom. i. Apparently the earliest of the superficial beds hitherto discovered is a remarkable deposit of yellow or white clay, which is to be seen, as to its chief exposure on the Head, at a point about 350 feet above the sea, near Gwydfyd farmhouse, at the upper part of the open glen between the north-eastern point of the Head and Pen y Dinas on the south-east, where it is worked in a quarry for exportation. This bed consists of siliceous sandy clay of very fine tex- ture with a large proportion of chert fragments, and lies here (as similar beds do on the Little Orme’s range) in a DEPOSITS AND ELEVATION.. 9 hole or pocket of the Limestone rock. There the boulder- clay has been traced overlying the deposit. No fossils have occurred to mark its age ; but it has the appearance of being in situ, and of having probably been deposited after the limestone had taken its present form. It has been fully described by a good geologist, Mr. Maw (Geol. Mag. ii., 1865), from whose account the fore- going description is abridged. Another, but less important, patch of the same deposit may be traced im a very similar position, namely, higher up the larger valley of the “Old road.” Mr. Maw did not find chert bands on Little Orme’s Head ; nor have I been able to detect any in the limestone of the larger hill; but there are traces of a cherty stratum amongst the grit- stone rocks which form the east end of the Telegraph-hill ridge. i. The next of the deposits are glacial and boulder-clays of a late age. These appear in four distinguishable forms. a. Probably the oldest of these is that described by Mr. Bonney as a bed of tenacious dark-blue clay, full of small pebbles of a dark slaty rock, rising 1 or 2 feet at the foot of the western cliff of the isthmus, and traceable for some distance below high-water mark. It may be that this and the following bed (4) are the same, seen under somewhat different conditions. A not dissimilar bed is well seen in the sections of the railway-cuttings near Bangor Station. That bed occurs in two strata, one full of small stones and coarse sand, and the other, an upper layer, with more clay and finer sand, and containing a few fragments of shell too small and too much worn to be determinable. It is, however, at a con- siderable elevation above the sea-level, and is not overlain by any boulder-clay. 6. A close, greyish, olive-coloured, rather sandy bed, with rounded stones of various rocks, comes up on the beach, 10 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD and occasionally at the bottom of the sea-cliff, on the west side of the isthmus. It is apparently without traces of shells. c. A chocolate-brown clay of close texture, with boulders (some scratched) and seaworn pebbles distributed through- out, and occasionally, but very rarely, slightly bedded, forms the general base of both eastern and western cliffs. This bed was best seen on the beach and at the foot of the low shore cliff in the eastern bay, where are now built the new stone wall and boat-stairs opposite Ty-gwyn in Llan- dudno. At this spot I have found characteristic fragments of Tellina solidula. Astarte arctica. Mactra solida. Cardium edule. The bed appears, but not so well marked, and not ex- hibiting fragments of shells, at the foot of the western cliff over the last-named and passing upwards into the next-named bed. The local exposure of strata in the western cliff is very various, and alters considerably, as each year exhibits a fresh face or, under the influence of rain and wind, a fresh disguise. Inch-measurements are of very trifling value. This third bed appears at the bottom of the ballast-cut- ting behind Colwyn Station, four or five miles east of Llandudno, under sandy clay and old beach-shingle. At that place I found good fragments of Sazxicava, Astarte arctica, and Cardium edule. The Astarte is distinctly a shell of Glacial age, and of common occurrence in the Moel Tryfaen beds, near Caernarvon. d. Upon the brown clay is a very similar bed of lighter- coloured, reddish, looser clay, with rounded and angular stones. It is exposed on the western cliff to the thickness of 20-30 feet, and in most of the superficial cuttings on the isthmus, as at the brickfields and in the new road from DEPOSITS AND ELEVATION. ia Diganwy Hotel, past Bryngosol, to the main road. In the west cliff, fragments occurred of Mya truncata. Cardium edule. Tellina solidula. Mytilus edulis. Mactra. Buccinum undatum. Collectors must be careful not to confound with genuine fossils from this bed the weathered but not worn fragments of Mytilus, Cardium, and Willow-pattern, which not un- frequently occur on the face of this section, and are due to tillage of the surface and some rain-wash. This seems to be a true boulder-clay. It is just dis- tinguishable at Llandudno from the bed below, whose Astarte it does not appear to share. The bed with similar fragments occurs at a 70-feet elevation above the bath- house. J may mention a very fine section of it near some white cottages on the road-side, at the eastern foot of Penmaenbach, to the west of Conway, showing, besides the usual promiscuous assortment, one fine horizontal bed of large boulders high up in the clay cliff. From the same bed, at a brickfield at the foot on the west side of Penmaen- bach, I have obtained worn shells of Littorina littorea and Fusus antiquus. Both of the Llandudno beds are repre- sented, as Mr. Binney has pointed out, in the Blackpool cliffs. The greater variety of species which figures in the Lan- cashire list* may be attributed to the occurrence there of larger beds of sand and shingle, apparently deposited under littoral (or at all events shallow-water) conditions very dif- ferent from, and possibly somewhat more recent than, those which alone can have prevailed amongst the rocky islets of the two Heads. The fragments from Llandudno are much more worn than at Blackpool. Mr. Maw identifies the boulder-clay as recurring to the south-east of the Head at a height of 170 feet in the Gwydfyd valley, and says it forms a terrace about the same height on the south side. * See Geol. Mag. ii. 298, 1865. 12 MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD I have not been able to satisfy myself of the existence of this bed elsewhere than at the side of the Gwydfyd valley, not far from the Bath-house, undisturbed; but the occurrence of travelled boulders and pebbles in sub- aerial beds, to be described presently, records its former existence at even higher levels than that just named. Thus, a single boulder of greenstone was found amongst angular fragments of limestone, talus, and superficial clay above Gwydfyd farm, at 380 feet above the sea. The foregoing deposits are those of sea-bottom,—the boulder-clay telling unmistakeably, in its great rounded or angular stones, of the beach-gravel carried along by the travelling ice of the drift ocean, or the débris of the glaciers of the rising land, lodged in the depths of a more or less profound sea. The beds have probably successively suf- fered great vertical denudation during the process of eleva- tion, and they are still subject to considerable horizontal waste from the west. The beach is covered with great boulders of greenstone, granite, slate, and other rocks, polished and sometimes scratched. The same boulder-clay appears in the shore cliff at the west end of Little Orme’s Head. IfI may offer a conjecture as to the period of the deposit of the upper or boulder-clay beds, I would say that it took place towards the close of the Glacial epoch, and was due to the redistribution of the more ancient northern drift, the remains of which it now covers, under the influence of the elevation and of the descent of glaciers from Snow- donia (in whose recesses the Astarte has been found on beaches), very long after the vicissitudes of the earlier period had removed much of the supermcumbent rock (already shaped by rain and frost before its first submergence) and had left a rocky sea-bottom filled up with Glacial clays and at the time rising and, though still under water, shaped much as we now see it. : I will presently give reasons tor thinking that the actual DEPOSITS AND ELEVATION. 13 elevation of each Head above the water-level has taken place since those seas bore icebergs, and in fact at a time more recent than the prevalence on this particular spot of land-ice. There are not wanting certain indications which may possibly imply a former continuity between the boulder- clays of Llandudno and Penmaenbach ; but this question and the consequent hypothesis of a subsequent diversion of the course of the Conway river from an ancient debouch- ment to the eastward into its present estuary do not fall within the scope of the present essay. B.Sea-beach and Beach-marks. In order of antiquity I take the highest first. Mr. Binney (Manchester Geol. Soc. Trans. 1861-1862, p. 99) has described what he calls a smgular bed of shingle at an elevation of 400 feet from the sea-level, at a point on the “old road,” a little to the east of where the road to St. Tudno’s Church branches off. This is a very peculiar deposit, and will be discussed in detail in the sequel. There are to be seen on most parts of the Head, where the limestone rock is bare, large isolated masses of the like stone, more or less rounded and weathered. One of these has been figured by the Rev. T. G. Bonney (Geol. Mag. iv. pl. xii.) apparently, though the statement is not definitely so framed, as an indication that the surface of the higher ground has in many cases been affected by ice. These blocks occur in considerable numbers on the north-western region of the Head. They lie on the bare rock, sometimes conformably, but oftener not, and are of course much weathered. Some have already been subjected to the more obvious disintegration of frost-splits, and he in frag- ments. There are two characteristic blocks of this kind near the eastern ends of two reefs of rock which cap the more precipitous portion of the southern declivity. 14, MR. R. D. DARBISHIRE ON GREAT-ORME’S-HEAD It seems to me out of the question to regard these blocks as perched blocks. They are uniformly of a stone ap- parently identical with the beds in their immediate neigh- bourhood, and may often be connected with a neighbouring reef of rock, both by the character of the stone and by the style of wearmg. to sip of an inch in diameter. In the centre of each peduncle they are about =}> of an inch in diameter. At dd are two pores, which are sections of two canals, running the entire length of the axis of the stro- bilus, and which serve in an important manner to identify homologous parts in different sections. These canals have a diameter of 74,5 of an inch, and the cells immediately surrounding them range from about z@s5> to teoa of an inch in width, these being much smaller than the rest. The dark and dense patches, e e, I believe mark the posi- tion of some important bundles of reticulated vessels to which I shall again have to refer. At fff are three of the pyriform spaces separating the primary peduncles. The transverse section of each of these is broadly ovate at its inner extremity, and acuminate in the opposite direction. On each side of this acuminate portion, and separated from it only by a very thin film of oblong cells, is the ovate basis of a smaller, but otherwise similar, space (g), at the peripheral end of which is a patch of tissue (h) somewhat denser than the rest, and which marks the starting-point of a spore-bearing peduncle or sporangiophore, which as- cends almost vertically into the substance of the strobilus. These sporangiophores are twenty in number, or double that of the primary peduncles. The remainder of this section consists chiefly of coarse cellular tissue, with the exception of the darkly shaded portions, 7 7, which are masses of spores. Owing to the peculiar inflections of the bractigerous disk given off from each node, no one continuous horizontal section can be made through its entire plane, as will readily be understood on reference to the restored vertical section of the strobilus, fig. 13, where 252 PROF. W. C. WILLIAMSON ON A NEW FORM the dotted line, x x, represents the direction of the hori- zontal section, fig. 3. From this it will be seen that, after giving off the ascending sporangiophores (/), the bracti- gerous disk continues its outward course for a very short distance, and then bends suddenly downwards, resuming its upward direction as it approaches the exterior of the stro- bilus. Asthe sporangia accommodate themselves to these curvatures, it follows that a section made in the line (fig. 13) x x will intersect the sporangia at its peripheral margin, as is done in the instance of fig. 3, @ 2. Fig. 4 represents a transverse section of the entire stro- bilus, made at an angle somewhat inclined to the central axis * ; hence, whilst in the part opposite to x it intersects the strobilus nearly in the same plane as fig. 3, throughout the remainder of the section (as at y) it has crossed the seg- ment somewhat higher up, revealing the structure of the central axis and of the sporangiophores, hh’, after their detachment from the bractigerous disk and their consequent separation from the axis. In this section we see the medul- lary cavity at a surrounded by the woody axis, the innermost part of which consists of the coalesced bases of the ten pri- mary peduncles. Lach of the latter exhibits the two small pores seen in fig. 3 d, and which obviously indicate con- tinuous canals, running vertically through the woody axis. The relations of the woody axis to the bractigerous disk and surrounding mass of sporangia have been somewhat dis- turbed by a rupture apparently due to some shrinking of the cone prior to fossilization ; but, notwithstanding this, we have no difficulty in identifying the various parts of the section. Thus at ¢ we have one of the primary pe- duncles flanked on either side by one of the large pyriform spaces, f f. At the peripheral extremity of this peduncle we see the rounded inner boundaries of the two smaller pyriform spaces, which, though somewhat disturbed, can * As indicated by the line w w in fig. 13. OF CALAMITEAN STROBILUS. 253 be traced up to the two well-marked sporangiophores h” h''. If we proceed right and left from this starting-point, owing to the obliquity of the section, we can trace the gradual divergence of the sporangiophores from the central axis, and their isolation amidst the masses of sporangia which they have supported—also the contraction of what I have termed the primary peduncles of the bractigerous disk nto mere prominent longitudinal ridges on the ex- terior of the central axis, like those on the stem of a Cala- mite, whilst the large pyriform cavities, in like manner, become deep grooves separating these ridges. In this figure little attempt has been made to delineate the compli- cated and interrupted outlines of the sporangia, 7 2, except at the peripheral margin, /, where their distinct continuity shows that we possess the outermost portion of the stro- bilus. In the interior of the structure, the arrangement of these sporangia has been much disturbed, apparently by imequalities in the mutual pressure to which they have been subjected, resulting from the growth of the spores. Fig. 5 represents the central portion of a transverse section made at a higher poimt than the last, corre- sponding to the line y y in fig. 13. The cylindrical axis surrounding the medulla (a) 1s now more sharply de- fined, owing to the absence from this internodal portion of the bractigerous disk. The homologues of the bases of the ten primary peduncles of fig. 4 are identified by the two small canals in each (c, c), which here approach the outer surface of the axis: we thus see, as I have already suggested, that these primary peduncles are merely nodal prolongations of ten somewhat rounded, project- ing ribs running longitudinally along the exterior of the central axis; these ribs, becoming increasingly promi- nent as they approach the node, both from above and from below, gradually converge, and at length coa- lesce, so as to enclose the intermediate grooves, which 254 PROF. W. C. WILLIAMSON ON A NEW FORM are thus converted into pyriform openings (/f) perforating the bractigerous disk. The vertical sectior, of which one side is represented in fig. 7, seems to indicate that the disk attains its greatest development a little below the actual node of the axis which is indicated by fig. 7 e, since at ¢ we have cellular tissue extended peripherally towards the bractigerous disk below, whilst at c’ we have a similar ex- pansion of the axis proceeding towards the next disk above, the next superior node (corresponding to e) not being contained within the section. The axis at the internodes (fig. 5) is closely invested by the mass of sporangia, the outlines of which are often more distinctly traceable here than in fig. 4; but in other respects the unfigured peripheral portion of the former section corresponds closely with the lower part of fig.4. At this part of the internode the spo- rangia have obviously no connexion with the central axis, beyond that of mutual contact; but the lines of their inter- sected walls can be traced, in several instances, radiating from the isolated sporangiophores. The entire thickness of the wall of the axial cylinder at this pomt is about =) of an inch at the ridges (fig. 5 c), and 3y of an inch at the intervening grooves. Fig. 6 represents a vertical section made through the centre of the segmentfigs.1and2. a isthe medullary cavity, bounded on each side by the woody axis. At ¢ we have a contribution from part of the internode immediately above the node, towards the formation of the bractigerous disk, k ; and from the latter there ascends obliquely upwards and outwards the sporangiophore, h. At k we find the bracti- gerous disk continuing its outward course for a short space in the horizontal plane, then bending suddenly down- wards in a sweeping curve, and resuming its upward course to support the bracts (4') investing the exterior of the strobi- lus. All the darkly shaded portions of this figure represent sporangial masses—the rounded portion, i, being especially invested with the cellular wall of this sporangium, showing OF CALAMITEAN STROBILUS. 255 that the latter structure originally filled the contiguous de- pression in the peripheral portion of the bractigerous disk. It may be observed that, in all the vertical sections, the disk is seen to receive vascular and cellular contributions, both from above and below the node to which it belongs, though chiefly the latter—a condition not unlike what occurs in the reproductive spikes of many living Equisetacez, where a similar thickening of the sporangiophores takes place. Fig. 7 exhibits the right half of a vertical section lke the last; but, from its importance, it is represented as more highly magnified. a is part of the medullary cavity, in immediate contact with which is the prosenchymatous tissue, everywhere forming the innermost part of the solid woody axis. The cells are oblong, and of various lengths. Sometimes they have rectangular septa, but more frequently they present obliquely overlapping ex- tremities. The structure of the outer part of the woody cylinder varies according to the line in which the vertical section has been made. We here find that the axis begins to enlarge at the centre of the internode, e’, and continues to do so gradually as we ascend to the node above. The enlargement is the result of additional prosenchymatous cells (c') added to the exterior of the longitudinal ridges. At f the section has laid open a narrow segment of one of the larger pyriform canals, fig. 3 f, throughout a great part of its length ; whilst at c’’ we have the thin film of prosen- chyma which has separated that canal from one of the smaller ones, fig. 3g. At the lower part of the section we have some important features exhibited. At eis the node, marked by a constriction of the medulla, arched over by a group of reticulated vessels. These are identical, both in their structure and arrangement at this point, with what I have described in Calamopitus. They spring from the medulla below the node, at an oblique angle, and arch over the node, returning to the medullary tissue at nearly the same angle as that with which they arose; but 256 PROF. W. C. WILLIAMSON ON A NEW FORM instead of terminating abruptly, they now proceed upwards (fig. 7, e’) parallel with the pith, forming the outermost portion of the external longitudinal ridge of the axis. Un- fortunately I possess no tangential section of this part of the structure; consequently Iam unable to speak with certainty respecting the superficial arrangement of these vessels ; but a careful study of the various sections has led me to the conclusion that there are two of these woody bundles im each external rib of the axis. I believe that their position in the transverse section is mdicated by fig. 3 e, or immediately external to each one of the longitudinal canals, fig. 3 d—which accounts for their position at the exterior of the ribs in the section fig. 5, c. If this ex- planation be correct (and I have little doubt about it), some important inferences are suggested by the fact. It indi- cates that these vascular bundles are the homologues of the woody wedges of Calamites, and that the small canals in like manner represent those of which, as Mr. Binney and others have poimted out, one forms the mnermost angle or starting-point of each woody wedge. From each node we find the cellular tissue c descending a short distance, but proceeding rapidly outwards to form the upper part of the next inferior bractigerous disk. At h we have the sporangiophore of the same disk, but forced in- wards, away from its normal direction, to pass upwards between the two sporangia 2 andl. It will be observed that this upper surface of the bractigerous disk is very different from the Jower one. In the latter, the gradually enlarged ribs ascend from the centres of the internodes, like ten buttresses, sustaining the disk with its sporangiophore and mass of sporangia. On the other hand, at the upper surface, the ribs, descending from the internode above, are but slightly enlarged ; hence a slight concavity in the disk is adapted to receive the inferior surface of the imner sporangium /, which rests upon it. OF CALAMITEAN STROBILUS. 257 Fig. 8 represents portions of two of the vessels from fig. 7, e, more highly magnified, and exhibiting the reti- culated character which has hitherto proved so distinctive of Calamopitus. 'They have a variable diameter of from sta to p45 Of an inch. The outlines of some of the sporangia are very distinct in fig. 7, the sporangium-walls (J, /') being more continuous and regular than usual, whilst the spores (é), indicated in the drawing by the dark mottled surfaces, are packed very closely round the main axis. Fig. 9 is a transverse section of one of the sporangio- phores from the unfigured part of the section of which fig. 5 is the central portion. Its dorsal surface, h, is rounded ; but its opposite or inner margin projects as a strongly defined keel ('), owing to two deep lateral exca- vations, which gives this part of the organism a compressed form. It chiefly consists of densely aggregated elongated cells, or prosenchyma, with vague traces of vascular tissue ; but in all the longitudinal sections, its structure is so dense and black that the details are not easily made out. The greatest diameter of this sporangiophore is about 745 of an inch, and its lesser or transverse diameter about 74; of an inch. The numerous spores are enclosed in sporangia, the structure of the investing membranes of which appear to be almost identical with those of the Calamitean strobili described by Mr. Binney and Mr. Carruthers. These sporangium-walls are cellular, the oblong cells being arranged vertically to the two surfaces of the membrane, which is about ;4, of an inch in thickness, whilst the in- dividual cells have a diameter of from yyy to aa5a Of an inch, the latter bemg the more usual dimensions. Exter- nally, the ends of the cells are generally plane (fig. 10, 1’), whilst their inner extremities (/) are somewhat convex and turgid ; but these differences are not constant. In some SER. III. VOL. IV. ji S 258 PROF. W. C. WILLIAMSON ON A NEW FORM instances these membranes can be traced continuously for considerable distances round the several sporangia; but in other cases they seem to have been disturbed and broken up by the swelling of the spores. Iapprehend that this derange- ment, combined with the regular symmetry and exquisite preservation of the vasculo-cellular portions of the cone, may be accepted as an indication that the spores had reached maturity, rather than been in a half-developed state. In all cases the undulating outlines of the sporangia indicate the same thing, the membranes having been apparently corrugated and shrivelled, their protective functions having been nearly fulfilled. The exact number of the sporangia clustered round each sporangiophore is not certain. I have not been able to trace more than three in many instances; but occasionally I find indications of a fourth. We may safely conclude from three to four to have been the normal number associated with each sporangiophore. I am unable also to make out accurately the posi- tion and extent of the surfaces attaching the sporangia to the sporangiophores. I have already pointed out the distinctness of the sporangial membranes immediately be- neath the external investing bracts on the left side of fig. 4. The spores (figs. 11, 12) exist as a dense mass of separate cells, packed closely together within the sporangia; but occasionally detached ones are imbedded in the translucent carbonate of lime with which parts of the fossil are infil- trated, so that their structure is not difficult to determine. They consist of an outer (2) and an inner cell-wall (7’), the latter obviously representing the primordial utricle of au- thors and enclosing some peculiar cell-contents. In some instances, as shown in fig. 12, these cell-contents are aggre- gated into a dark well-defined central mass; but in others, as in fig. 11, this mass has no defined outline, being gra- dually merged in the inner cell-membrane (#) which en- closes it, whilst occasionally it is absent. I was at first OF CALAMITEAN STROBILUS. 259 inclined to believe that the dark central portions seen in fig. 12 were the spores, enclosed within a true cell; but after a very careful conjoint examination made by Mr. Car- ruthers and myself, we satisfied ourselves that each cell in its entirety constituted a separate spore. They have an average diameter of from 34> to =}, of an inch, whilst the dark central mass is from 34, to 34, of an inch. As arule, I distrust most detailed restorations of fossil plants; but in this instance the specimen is in such exquisite preservation that there can be no doubt as to the general plan of its construction. Fig. 13 may be regarded as a vertical section of its five lower seg- ments, of which the sporangia are supplied to two of the lower ones, whilst the upper two show the relations of the axis to the bractigerous disk and its appendages. That the pith has been fistular in the fully developed cone I infer from the beautiful preservation and sharply defined outline of the cellular tissue lining the interior of the woody axis, combined with the presence, within the cavity, of perfect rootlets of Stegmaria, the latter especially proving that the axis was hollow when the strobilus fell into the mud which the Stagmaria-roots were permeating with their ubiquitous fibres. We have next to consider the probable relations of this strobilus to other Coal-measure plants, and especiaily to the somewhat similar structures described by Mr. Binney* and Mr. Carrutherst, the specimens studied by the latter gentleman having been also derived from Mr. Binney’s collection, and being identical in nature with those figured by him. Inall essential features my plant corresponds with these, as well as with that described by M. Ludwig and referred to by Mr. Carruthers in the above memoir. Mr. * Loc. cit. + “On the Structure of the Fruit of Calamites,” by Wm. Carruthers, Esq., F.L.8., Journal of Botany, Dec. 1867. Ss 2 260 PROF. W. C. WILLIAMSON ON A NEW FORM Carruthers’s careful description makes a comparison of the points of agreement and difference easy. Describing Mr. Binney’s specimen he says, “‘ At regular intervals the axis gives off whorls of appendages which are alternately foliar and fruit-bearing.” We here note the first difference. In my example each node gives off both these elements. “The foliar whorl consists of twelve leaves, which pro- ceed horizontally from the axis until they reach the circum- ference of the strobilus, where they take an ascending direction. The leaves are united together by their margins until they reach the outside of the fruit, and form a con- tinuous septum, dividing the strobilus into a series of chambers.” This description, allowing for the inflections which I have described, identifies the structure spoken of with my bractigerous disk. Thus far we find the essential conformation of the two fruits exhibiting a close correspond- ence. Mr. Carruthers says, “ Between each foliar whorl there is a verticil of leaves specially developed for the support of sporangia.” On this point the two types differ. Instead of this alternation, in my specimen the fruit-bear- ing organs, or sporangiophores, are developed at each node instead of at alternate nodes ; and in the place of shooting out at right angles directly from the central axis, they spring obliquely, or almost vertically, from the upper sur- face of the foliar verticil or bractigerous disk. In Mr. Carruthers’s description, the end of each of these sporan- giophores is described as being peltate. In only one instance have I been able to trace the upper part of the sporan- giophore in my example; and, like the specimen described by M. Ludwig, it appears to have been a thorn-like process, unprovided with any peltate extremity. The structure of the sporangium-wall is identical in the two cases; and the arrangement of the sporangia around the sporangiophore is also similar, making allowance for the vertical position of the latter in my instance, and its horizontal one in OF CALAMITEAN STROBILUS. 26] Mr. Binney’s. “ The spores are simply globular bodies, fre- quently exhibiting an outer and an inner wall.” This de- scription also tallies with my own; but Mr. Carruthers continues, “ Sometimes, however, they appear to be com- posed of a single wall; and then the outer wall is represented by lines more or less separated from the spores. These 1 believe to be elaters, similar in structure to those of Equisetum.”’ I have found spores exhibiting something of this appearance when the outer cell-membrane had been broken up, either by contraction or, more especially, during mineralization ; but I am satisfied that my specimen con- tains no elaters. In the structure of the central axis, again, we have a difference. In Mr. Binney’s specimens the centre of that axis is occupied by a bundle of scalariform tissue. Nothing of the kind exists in my plant. Its central portion presents every appearance of having been fistular, or only occupied, in its young state, by cellular tissue. The only vessels to be seen are in the woody axis, where they are reticulated and unaccompanied by any scalari- form ones. At the same time, there can be no doubt that the two types are constructed upon the same general plan, the differences which they present being but generic and not ordinal ones. They resemble each other too closely in their common features to leave a doubt that if the one is Calamitean so also is the other ; and since no one appears to doubt that such is the character of Mr. Binney’s strobilus, I may fairly claim the same rank formy own. What, then, is the signification of the points in which they differ? It will be remembered that the Calamitean stem which I described under the name of Calamopitus was characterized by the possession of reticulated vessels instead of the sca- lariform ones common in other types of Calamite, and by a peculiar arched arrangement of those scalariform vessels wherever they crossed the node, which latter arrangement is common to all the types of Calamite of which I have 262 PROF, W. C. WILLIAMSON ON A NEW FORM hitherto seen the internal structure; and, in addition, Cala- mopitus has its projecting ridges composed of longitudinal wedges of vascular tissue, separated by intervening ones of prosenchyma. Fig. 8 shows that my strobilus exhibits the first of these characteristics ; figure 7 e displays the second; whilst, if I am correct in my interpretation, we find the third feature echoed in the longitudinal arrangement of the vascular bands (fig. 7, ee’), and in the relationship of those bands to the small longitudinal canals (fig. 3, d), as well as to the masses of cellular prosenchyma (fig. 7, ¢ c’) which separate them. Bearing in remembrance the apparently obvious fact that my strobilus is an indisputable Cala- mitean fruit, and that Calamopitus is the only Calamitean stem hitherto described possessing the true reticulated vessels which it exhibits, it becomes more than probable that some close relationship exists between the two plants. If they are not actually the stem and fruit of the same species, at least the fruit must have belonged to some hitherto undiscovered stem with reticulated vessels closely allied to Calamopitus*. It is true that,im the specimen of the latter which I described, I could not trace the small canal seen at the inner angle of the woody wedges of other Calamites ; but I have already found specimens which indicate the possibility that this apparent absence may have been due to mineralization masking, by dark carbonaceous deposits, what may have existed in its mini- mum rather than its maximum degree. At first there seems to be a difficulty in admitting the association of a cryptogamic fruit with an exogenous stem ; but we do not escape this difficulty by refusing to accept my suggestion. Noonecan doubt that Calamopitus is merely * Since this memoir was read I have obtained stems with reticulated vessels, but otherwise like Calamodendra, to which the strobilus may have belonged, OF CALAMITEAN STROBILUS. 263 a highly developed Calamitean plant ; neither does any one now doubt that the fruit of Calamites was cryptogamic. Besides which, we must remember that a cambium-layer and an exogenous mode of growth are still found associated with Cryptogamic inflorescence in all the living Marsile- ace; so that the possibility of the combination which I have suggested is in strict accordance with conditions known to exist, instead of being, as some have supposed, abnormal, and contradicted by all modern experience. The only other known Coal-measure plants in which re- ticulated structures abound are those for which I have proposed the name of Dictyoxylon*. But whatever objec- tions may suggest themselves to identifying the strobilus with Calamopitus militate in a tenfold degree against a similar identification with Dictyoxylon. The latter is not only exogenous in growth, but probably a true Exogen in the technical sense of the word, if not even an actual Conifer; hence there is the greatest improbability that it bore a Cryptogamic strobilus. But, on the other hand, admitting that Calamopitus and this strobilus are equally Calamitean in type, that they exhibit essential features which they possess in common, and that in both cases these features poimt to a higher organization than is usual amongst the more ordinary Calamites, I am justified in concluding that the subsistence of a close relationship be- tween the two fossil plants is more than probable. As- suming this probability to be established, what light does the fact throw upon the affinities of the above fossils with recent plants? I find in my strobilus, as already stated, nothing like Equisetiform elaters. The spores are simple cells, which is also the case with recent Equisetiform spores in their young state. But, for reasons already given, I believe the fruit described to have been fully developed. Consequently, so far as it goes, it gives no support to the * Monthly Microscopical Journal, No. vii. August, 1869. 264 PROF. W. C. WILLIAMSON ON A NEW FORM idea that Calamopitus was Equisetaceous; on the other hand, whilst the stem was more complex than that of living Equisetacez, the fossil spores are more simple in their or- ganization than in the recent genus. The fruit sustains the conclusion at which I arrived from a study of the stem, that Calamopitus possessed a higher organization than the known forms of Calamodendron. The exogenous growth of the stem by the regular addi- tion of new vascular bundles to the exterior of the woody axis, indicates the possession by these plants of a cambium- layer such as exists in the living Marsileaceze. Unfortu- nately we know too little of the cortical layer of Calamites to affirm any thing respecting it; but it becomes of great importance to ascertain whether it was persistent, receiving internal additions from the cambium-layer (in which case we should expect to find itin some degree ruptured exter- nally), or whether it was thrown off annually and annually reproduced as in the living Isoétes. As yet we possess no facts throwing light upon either of these problems* ; but when we obtain their solution, we shall doubtless find in it the explanation of the great differences observable, both in the aspect of the cortical layer of fossil Calamites and in the opinions of authors respecting its thickness and aspect. Mr. Butterworth informs me that he found the specimen here described in a nodule from the upper foot-coal at Roe Buck, in Strinesdale, Saddleworth. INDEX TO PLATES VIL., VIII., & IX. Tig. 1. Lateral aspect of the lowest segment of the specimen, enlarged four diameters. Fig. 2. Inferior surface of the same segment, showing the pyriform canals around the medulla, a; 4, margin where the bractigerous disk divides into separate bracts. * This bark has now been obtained, and will shortly be described.— April 21, 1870, ~ OF CALAMITEAN STROBILUS. 265 Fig. 3. Transverse section of part of central portion of fig. 2, made in the line x x, fig. 13: ¢, c, primary peduncles; d, d, longitudinal canals of axis; e, e, bundles of reticulated pleurenchyma; f, f, larger pyriform apertures in the bractigerous disk; g, g, smaller apertures ; h, h, bases of the sporangiophores ; 7, sporangia. Fig. 4. Slightly oblique transverse section of one of the upper segments of the strobilus, made in the line w w of fig. 13, passing through the bractigerous disk opposite to «x (fig. 4), and a little above it in the rest of the section: a, medulla; ¢, primary peduncles ; , h’, h’’, sporangiophores; 7, sporangia; J, cellular sporanginm- walls, seen in section. Fig. 5. Central part of a transverse section of half of the segment figs. 1 and 2, made in the plane y y of fig. 13: a, medulla; e¢, c, ex- ternal ridges of the central axis, identical with the primary pe- duncles of fig. 4; 2, sporangia. Fig. 6. Vertical section of segment figs. 1 and 2: a, medulla; c. central axis ; h, sporangiophore ; 7, 2’, sporangia; #, bractigerous disk; %’, bract. Fig. 7. Lateral half of a vertical section of one of the upper segments: a, medulla ; c, cellular tissue descending from the node e towards the bractigerous disk below; ¢', prosenchyma ascending towards the next bractigerous disk above; ¢”, thin layer of prosenchyma separating the larger pyriform canal f from one of the smaller ones not seen in the section ; e, arches of reticulated pleurenchyma forming the node; e’, the same pleurenchyma prolonged upwards, external to the prosenchyma of the axis; 2, sporangiophore be- longing to the bractigerous disk c; 7, 7, spores; /, inferior wall of a sporangium resting upon the bractigerous disk ¢; J’, ex- ternal wall of the sporangium 2. Fig. 8. Two reticulated fibres from 7 e, more highly magnified. Fig. 9. Transverse section of upper part of a sporangiophore: h, peripheral margin; ', inner margin. Fig. 10. Transverse section of part of a sporangium-wall: /, inner surface ; Z', outer surface. Figs. 11, 12. Detached spores: 2, outer cell-membrane ; 7’, inner-cell mem- brane. Fig. 13. Restored vertical section of five inferior segments of the strobilus : a, medulla; 4, outer margin of bractigerous disk; ¢, central axis ; 4, sporangiophores ; 7, 7, sporangia; %, external bracts ; /, sporangium-walls; ww, plane of section, fig. 4; x x, plane of section, fig. 3; y y, plane of section, fig. 5. 266 MR. R. A. SMITH ON A SEARCH FOR XX. A Search jor Solid Bodies in the Atmosphere. By R. Anevus Situ, Ph.D., F.R.S., &c. Read March 31st, 1868. I nave so frequently for many years attempted to find, and have found, organic substances which have passed from the air into the liquids in which they were collected, that perhaps the Society will scarcely attend to another attempt, although it indicates, I think, some progress. It was in the year 1847 that I first collected what I believe was matter from the respiration and perspiration, and found that as it was kept it grew into distinct confirmed forms. Whilst examining some matters relating to the cattle- plague, I found one or two remarkable points. I had before that time used aspirators to pass the air through liquids, except in the oxidation experiments. At that time I used simply a bottle which contained a little water. The bottle was filled with the air of the place, and the water shaken in it. The difference of air was remarkable. A very few repetitions would cause the liquid to be muddy, and the particles found in many places were distinctly organic. Before speaking of my last experiment, it may interest the Society first to hear of a few of these previous at- tempts, the latest made till recently. I shall therefore read from a report to be found in the appendix to that on the cattle-plague. “Mr. Crookes also brought me some cotton through which air from an infected place had passed. It was ex- amined at the same time. Taking the cotton in the mass, nothing decided was seen ; but when it was washed, some of the separate films were coated over with small nearly round SOLID BODIES IN THE ATMOSPHERE. 267 bodies presenting no structure, or at least only feeble traces of it, and perhaps to be called cells. I had not sent gun-cotton, as I intended, to Mr. Crookes, fearing the rules of the post; otherwise there would have been more certainty that the bodies spoken of did not exist previously on the cotton. However, Mr. Dancer, who has examined cotton with the microscope oftener than most persons, even of those experienced in the subject, had never observed a similar appearance. “The liquid had also a number of similar bodies floating in it. “Tt was then that Mr. Crookes sent a liquid which he had condensed from the air of an infected cowshed at a space a little above the head of a diseased cow. ‘This was also examined, and it presented similar indications of very numerous small bodies. Not being a professed micro- scopist, I shall not attempt a description, but add that they clearly belonged to the organic world, and were not in all cases mere débris. We found also one body a good deal larger than the rest; it resembled somewhat a Para- mecium, although clearly not one. “We found no motion whatever; and only this latter substance could be adduced as an absolute proof of any living organized being present. Next day I examined the same liquid; and, whether from the fact of time being given for development or from other causes, there was a very abundant motion. There were at least six specimens in the field at a time, of a body resembling the Kuglena, although smaller than I have seenit. When these minute bodies occur, it is clear that more may exist; and germs in this early stage are too indefinite to be described. The existence of the vital spark in the organic substances in the air alluded to is all I wish to assert, confirming by a dif- ferent method the observations of others. It might, of course, be said that since the bottle was opened at Mr. 268 MR. R. A. SMITH ON A SEARCH FOR Dancer’s the air at that place may have communicated them. I answer that, before it was opened, a good glass could detect floating matter ; some of it, however, as in the microscope, proved. indefinite enough. “ Finding this, and fearing that the long time needful to collect liquid from the atmosphere might expose it also to much dust, I used a bottle of about 100 cubic inches dimensions, and putting into it a very little water, not above five cubic centimetres, I pumped out the air of the bottle, allowimg the air of the place to enter. This was done six times for each sample, the water shaken each time, and the result examined. This was done with the same bottle that was used in my early experiments with permanganate, and by the same method, except that water instead of that salt was used. At first considerable num- bers of moving particles were found; but it was needful to examine the water used, and here occurred a difficulty. It was not until we had carefully treated with chemicals and then distilled the water again and again that we could trust it. Particles seemed to rise with the vapour; and if so, why not with the evaporating water of impure places. ‘‘ Having kept an assistant at the work for a week, and having myself examined the air of three cow-houses, I came to the conclusion that the air of cow-houses and stables is to be recognized as containing more particles than the air of the street in which my laboratory is, and of the room in which I sit, and that it contains minute bodies, which sometimes move, if not at first, yet after a time, even if the bottle has not been opened in the in- terval. There is found in reality a considerable mass of débris, with hairs or fine fibres, which even the eye, or at least a good pocket-lens, can detect. After making about two dozen trials, we have not been able to obtain it other- wise. Even in the quict office at the laboratory there seemed some indications. SOLID BODIES IN THE ATMOSPHERE. 269 “J found similar indications in a cow-house with healthy cows; so I do not pretend to have distinguished the poison of cattle-plague in these forms ; but it is clear that where these exist there may be room for any ferment or fomites of disease; and I do not doubt that one class is the poison itself in its earliest stage. It would be inter- esting to develope it further. ““T have recorded elsewhere that I condensed the liquid from the air of a flower-garden, and found in it, or ima- gined I found, the smell of flowers. I do not remember that I looked much to the solid or floating particles, think- ing them to be blown from the ground; but it does not affect the result, whether they be found constantly in the air or are raised by the action of currents. Lately I tried the same plan on a larger scale. A bottle was filled with air and shaken with water. The bottle was again filled and shaken with the same water ; and this was repeated 500 times, nearly equal to 2% million cb.c., or 2495 litres*. As this could not be done in a short time, there was considerable variety of weather—but chiefly dry, with a westerly wind. The operation was conducted behind my laboratory, in the neighbourhood of places not very clean, it is true, but from which the wind was blowing to other: parts of the town. I did not observe any dust blow- ing ; but if there were dust, it was such as we may be called on to breathe. The liquid was clouded, and the unaided eye could perceive that particles, very light, were floating. When examined by a microscope, the scene was varied in a very high degree; there was evidently organic life. I thought it better to carry the whole to Mr. Dancer and to leave him to do the rest, as my knowledge of microscopic forms is so trifling compared with his.” Appition, Marcu 1870. I certainly considered that I saw motion caused by * T think the total quantity is not correct ; but it is unimportant. 270 MR. J. B. DANCER ON THE SOLID PARTICLES life; Mr. Dancer says, “‘few living organisms were no- ticed.”” However, I defer to him in all matters con- nected with the microscope. There were many forms evidently organic, although not in motion. My belief was that they might be developed by care, as I had treated others similarly many years ago. In a memoir “On the Air and Water of Towns” (Report of the British Association, 1848), speaking of matter from the breath, I said, “ If it be allowed to stand for a few days (about a week is enough), it will then show itself more decidedly by becoming the abode of small animals,” &c. ; and when speaking of the condensed matter on glass and walls, it was said, “If allowed to stand some time, it forms a thick apparently glutmous mass; but when this is examined by a microscope, it is seen to be a closely matted confervoid growth, or, in other words, the organic matter is converted into conferve, as it probably would have been into any kind of vegetation that happened to take root.”’ I was quite familiar, therefore, with the idea of developing these germs; the matter is found in the exhalations, and on that they may feed. It seems as if a choleric germ or a plague germ might grow there indiffer- ently; and I do not see any thing more mysterious than natural action, which, however, is wonderful enough, XXI. Microscopical Examination of the Solid Particles collected by Dr. Angus Smith from the Air of Manchester. By J. B. Dancer, F.R.A.S. Read March 31st, 1868. Tue air had been washed in distilled water, and the solid matter which subsided was collected in a small stoppered FROM THE AIR OF MANCHESTER. pares | bottle, and on the 13th of this month Dr. Smith requested me to examine the matter contained in this water. An illness prevented me from giving it so much attention as I could have wished. The water containing this air-washing was first ex- amined with a power of 50 diameters only, for the purpose of getting a general knowledge of its contents; afterwards magnifying-powers varying from 120 to 1600 diameters were employed. During the first observations, few living organisms were noticed; but, as it afterwards proved, the germs of plant and animal life in a dormant condition were present. I will now endeavour to describe the objects found in this matter, and begin in the order in which they appeared most abundant. ist. Fungoid Matter.—Spores or sporidia appeared in numbers ; and, to ascertain as nearly as possible the nume- rical proportion of these minute bodies in a single drop of the fluid, the contents of the bottle were well shaken, and then one drop was taken up with a pipette; this was spread out by compression to a circle $ an inch in diameter. A magnifying-power was then employed which gave a field of view of an area exactly 10ooth of an inch in diameter, and it was found that more than 100 spores were contained in this space ; consequently the average number of spores in a single drop would be 250,000. These spores varied from the 10,o0o0th to the §0,oooth of an inch in diameter. The peculiar molecular motion in the spores was observable for a short time, until they settled on to the bottom of the glass plate; they then became motionless. The mycelia of these minute fungi were similar to that of rust or mildew (as it is commonly named), such as is found on straw or decaying vegetation. When the bottle had remained for 36 hours ina room at a temperature of 60°, the quantity of fungi had visibly in- 272 MR. J. B. DANCER ON THE SOLID PARTICLES creased, and the delicate mycelial thread-like roots had completely entangled the fibrous objects contained in the bottle and formed them into a mass. On the third day a number of ciliated zoospores were observed moving freely amongst the sporidia. I could not detect any great variety of fungi in the contents of the bottle ; but I cannot presume to say that all the visible spores belonged to one species; and as there are more than 2000 different kinds of fungi, it is possible that spores of other species might be present, but not under conditions favourable for their development. Some very pretty chain-like threads of conidia were visible in some of the examinations. The next in quantity is vegetable tissue. Some of this formed a very interesting object, with a high power, and the greater portion exhibited what is called pitted struc- ture. The larger particles of this had evidently been par- tially burnt and quite brown in colour, and were from coniferous plants, showing with great distinctness the broad marginal bands surrounding the pits; others had reticulations small in diameter. They reminded me of perforated particles so abundant in some kinds of coal. The brown or charred objects were probably particles of partially burnt wood used in lighting fires. Along with these reticulated objects were fragments of vegetation, resembling in structure hay and straw and hay seeds, and some extremely thin and transparent tissue showing no structure. These were doubtless some portions of weather-worn vegetation. A few hairs of leaves of plants, and fibres similar in appearance to flax, were seen ; and, as might have been expected in this city, cotton fila- ments, some white, others coloured, were numerous—red and blue being the predominant colours. A few granules of starch were seen by the aid of the polariscope; and several long elliptical bodies, similar to the pollen of the lily, were FROM THE AIR OF MANCHESTER. 21o noticed. After this’dust from the atmosphere had been kept quiet for three or four days, animalcula made their appearance in considerable numbers, the monads being the most numerous. Amongst these were noticed some com- paratively large specimens of Paramecium aurelia, in com- pany with some very active Rotifera; but after a few days the animal life rapidly decreased, and in twelve days no animalcula could be detected. Hairs of Animals.—Very few of these were noticed, with the exception of wool; of this both white and co- loured specimens were mixed up along with the filaments of cotton. After each examination as much of the drop of water as could be collected by the pipette was returned to the bottle, im order to ascertain if any new development of animal or vegetable life would take place, and the stopper of the bottle was replaced as quickly as possible to prevent the admission of the particles from the air in the room; and I am tolerably certain that the objects named in this paper are those which the bottle contained when Dr. Smith brought it to me. The particles floating in the atmosphere will differ in character according to the season of the year, the direction of the wind, and the locality in which they are collected, and, as might be expected, are much less in quantity after rain. The small amount of fluid now remaining in the bottle emits the peculiar odour of mildew; and at present the fungoid matter appears inactive. For the purpose of obtaining a rough approximation of the number of spores, or germs of organic matter contained in the fluid received from Dr. Smith, I measured a quantity by the pipette and found it contained 150 drops of the size used in each examination. Now, I have previously stated that in each drop there were about 250,000 of these spores; SER. III. VOL. IV. Jt 274 MR. G. V. VERNON ON THE MEAN and as there were 150 drops, the sum total reaches the startling number of 373 millions; and these, exclusive of other substances, were collected from 2495 litres of the air of this city*—a quantity which would be respired in about 10 hours by a man of ordinary size when actively employed. I have to add that there was a marked absence of particles of carbon amongst the collected matter. XXII. On the Mean Monthly Temperature at Old Trafford, Manchester, 1861 to 1868, and also the Mean for the Twenty Years 1849 to 1868. By G. V. VeERNon, F.RLACS., FMS: Read before the Physical and Mathematical Section, December 7th, 1869. In Vol. I., 3rd Series, of the Memoirs of the Society, in a paper “On the Irregular Oscillations of the Barometer at Manchester,” I gave reductions of the mean monthly tem- peratures observed by myself for 1849 to 1860, and in the present communication I have given the values for the succeeding years down to the end of 1868, completing a period of 20 years. It is scarcely necessary to remark that these values have all been carefully reduced to the Greenwich standard, and corrected by means of the Tables of Diurnal Range, computed and published by Mr. Glaisher. As will be seen by the notes appended to Table I., I have been indebted for a few months’ observations to Mr. Mackereth’s observations, made at Eccles, and which closely represent those made at Old Trafford. * Behind Dr. Angus Smith’s laboratory. MONTHLY TEMPERATURE AT OLD TRAFFORD. 275 Table II. contains the difference of the mean tempera- ture of each month from that of the whole period, 1849 to 1868; but unfortunately the month of August is almost entirely deficient in the earlier series, and this is a gap I see no chance of filling with observations made at any sta- tion which would be at all fairly comparable with the re- mainder of the series. The mean temperatures of the months of the various periods have been as follows :— 1849 to 1860.| 1861 to 1868.| 1849 to 1868. ° oO Lo) January ......... 38°3 37°2 37°8 Wepruary ......<.. 37°8 38°9 38-2 A a Ary 40°1 40°8 LAT rere 46°6 46°8 4.6°6 HA Giant entends.« 51°8 Cy: §1°7 BEMLO RS S25 ke kale 575 564 57°0 BR as oh servis ns 60°5 58°3 59°6 PRROUSE 0c. .vcsees. aes 57°6 58°7 * September ...... aS 2 551 551 Eo 48°5 49°0 48°7 November ...... 412 4I'l 41'2 December ......... 38°9 40°4 40°4 | a ake 47°3 47°9 The mean of the period 1861 to 1868 appears to have been on the whole rather colder than the average of the last twenty years, and apparently chiefly owing to the lower mean temperature of the month of July—July only exceeding 60°°0 in two years, 1865 and 1868, whilst in the earlier period July in six years exceeded 60°0, viz. in 1850, 1852 (67°°9), 1854, 1855, 1857, 1859. On examination of the mean variations of temperature for each month (Table II.), we find that the greatest amount of variation of the mean monthly temperature may be expected in February, and the least in October ; * From g years only. t 2 276 MR. G. V. VERNON ON THE MEAN or, arranging the months in their order of amount, we have :— fo} ° Oetober |).5.. $3553.42 1°50 Mearohi 4: 37i7ihee 207 p10) il eae oR 167 Daly abet cp eas 2:35 September ......... 1°89 Wovember ......s00 (2°37 May ..t if: . tia I'gt PAMESUISENS: . NIZA rae oe 2°61 January) .:ceus--o-: 2°02 December... - ase... 3°01 a) UND acne tteiss cee 2°06 Pebruary <3... <-.2.. 3°26 One point in this seems somewhat curious ; and that is, that the wettest and driest months should be lable to about the same changes of temperature ; the distribution seems very irregular, months widely apart coming next one an- other as regards this element of temperature. At the bottom of Table II. I have given the values of the probable variation of mean temperature for each month, computed from my own observations for the twenty years; and as the late Manuel J. Johnson gave similar values, computed from Dalton’s observations, 1794 to 1818 (Radcliffe Observations, vol. xv. 1854), I annex them for comparison. Dalton. Old Trafford. 25 years, 1794 to 1818. 20 years, 1849 to 1868. ° ° GAMUALY, “cadgepe- nese ay) + 1°80 Mebriany’.ii) sce: .ssacce 1°8 3°50 Marchy (2. Berries 1°6 1°93 Apri 2 fet eeteeyes 2% 1°49 May seman eeer soese ce 1'9 1°70 PUNE AS. Aeneas ade 1°6 1°84 dal Yesade sit yserett ae a8 1°8 2°09 AMBUBG | ecco at ened 1'2 2°48 Sepbemiber® Geancqacctete 16 1°68 October t:). 20. biaah t 1'7 1°93 November... 44.5. f-9/6 2°0 20s December p.car. ocho +1°8 +2°68 There are evidently great discrepancies between the two series of values, which it is quite out of my power to ex- plain ; but reference to the monthly means for Old Trafford MONTHLY TEMPERATURE AT OLD TRAFFORD. 277 show that the probable variations during the period 1849- 1868 must have been much greater for some of the months than those given from Dalton’s earlier period, especially in the month of February. In 15 years of the Old-Trafford observations, the variation of the mean temperature of Feb- ruary from the mean of the period exceeded 1°8 (the amount from Dalton’s observations) very considerably. The same may be said of other months, but not to the same extent. Taste 1.—Mean Monthly Temperature at Old Trafford, Manchester, 1861-1868. Year. Jan.| Feb.|Ma .Apr.|May|June|July|Aug.| Sep.| Oct./Nov.! Dec. id ° ° O° ° oO ° ° ° ° ° ° ° 1861 | 35°0) 40°0| 43°0) 44°4] 49°3/ 56°6] 59°3)...... 55°2| 52°38) 38°0) 39°5 1362 38°1| 410] 42°0| 41°2| 47°38) 48°0] 56°7| 58°0| 54°7| 49°1| 36°38) 43°0 1863 | 42°4) 41g) 43°8) 47°6| 50°9) 57°0) 51°5) 52°4) 47°7| 48°9| 45°0 42°9 1864 | 35°6| 35°2| 38°8) 48°3) 54°2) 5670) 58°3| 55°6| 54°7| 49°0| 43°0 48°5 1865 | 35°0) 35°5| 36°5| 50°5| 53°9| 59°8| 61°6) 58°13) 60°9| 49°0) 43°1) 41°9 1866 =| 39°7| 34°7| 35°5| 47°3| 48°9| 59°6] 57°0) 57°5) 53°8| 49°0| 43°7) 41°6 1867 — | 33°2) 39°9| 37°2| 48°7| 53°3/ 56°6| 58°4) 60°5) 56:2) 47°7) 38°7) 38-4 1863 — | 38°9 42°38) 43°8) 46°2| 55°3/ 57°5| 63°3) 6173) 57°6) 46°6) 40°8) 4art — —— | —_-_ | ———_ | —————. Means, 1361 to >) 37°2 38°9) 40°3| 46°8| §1°7| 56°4) 58°3/ 57°6] 55°1| 49°0| 41°1| 4074 August, 1862.—Determined by reduction from the ob- servations made at Eccles by Thomas Mackereth, Esq., F.R.A.S. I may remark here that our observations are nearly identical, or, where different, seem to be so almost by a constant difference. January, 1863.—From Mr. Mackereth’s observations. April, May, June, July, August, and September, 1868.— Taken from Mr. Mackereth’s observations. 278 MEAN MONTHLY TEMPERATURE AT OLD TRAFFORD. *SUOTPBLIBA 89.2 II £€.1 gg.I gv.z 60.2 Vg.1 oL.1 64.1 £6.1 So.€ Og.I { arqeqoag 10.£ Lee oS. 69.1 19.7 Seed 90.7% 16.1 Lg.1 BIR A gz.£ ZO.6— [eesee SUBOTT Let t.o— 1.2— S.t+ g.t+ L.e4- S.o+ 9.£+ v.o— o.f+ g.b+ I.1-+ 89g O.7— $.t— o.1— 101+ g.I+ Z1I— b.o— 11+ I.t+ 9. — L£.u+ 9.b— Logi Z.I+ S.c+ £.o+ €.1— Z.1I— 9.t— g.t+ g.o— L.o+ £.5 — $.£— 6.1-+- 9981 S.1-+ (See ¢.0-+- g.s+ 9.0— O.2+ g.co+ Z.t+ 6.64 t.y— L.z— 8.2— Sggt 1.g+ g.I+ £.0+ +.0— re = ar Or S.2+ Li1+ (a of — C.0— t9gI §.t+ g.f-+- Z.0-+ $.L— £.9— 1.g— 0.0 8.0.— O5+ of + g.€+ 9.b-+ Egger g.t+ +.b— b.o+ t.o— L.o— 6.2— 0.6 — 6.£ — $.$— Z.1+ B.o+ £.0+- ZQQI 6.0- Ghee LiV=t- BiO=te) 1h, tee f.o— t.o— b.z— Z.7— Z.o+ g.1-+ 8.0— I9gt 6:Se zZ.I— nos ecieee” bale ae escls O.7— g.1— B.t+ Z7.o— o.I — Leé— 1.0o— OggI £.9— g.1— 2.0 D.Qates «|e see Loyt+ Z.E+ 9.t+ v.1— o.b+ 6.2. €.e-+ 6Ser b.o+ O.7— oe 1.b+ o.f-+ Li— f.g+ g.1— Z.0— Z.0— 6.5— 1.0+ gSgr opt g.t-+ £64 9.z+ ab+ @er= 7+ o.1+ Z.0— O.n-+ 1.I-+ f.1— L£Sgr 61 O.t— Bets Go ee 6.0— f.1— S.1— 9.0-++ £.0o+ 6.2+ 1,0— gS gt g.b— f.0+ 2.0m ZO jleesse: Z.o+ 1.0+ Z.£— S.o— 9.t— 9.6— I. — SSgr g.0— 6.0— fas bea Pivots. Sige nee L.o+ I.o+ 9.0+ B.o+ Z.o+ g.o+ 1.o— bSgr a pea Sots pista Ol ite se O.1— g.I+ 1.0— O.I — 9.7 — v.S — B.o-+ ESg1 g.v+ g.£-+ Ti SiO— ip. Serer f.g+ g.1+ O.1+ v.I+ f.0-+ g.I+ Z.o+ 7SQr €.0-+ 9.5 — g.7+ oy — Boscia Pay —— I DOGH (pire |) ocean Lau+ ZI+ g.£+ ISgr 6.0— Le+ io eT et glue aces g.0o+ g.I+ Z.1I— 17+ 0,0 6.54 v.5 — OSgr eae Let 9.0— 0,1 + sisisiiee Z.0+ Lo— g.1+ 6.1 — 0.2-+ Sane | lg sacle 6begr ° ° ° fo) ° ° ° ° fo) ° ° ° “00(T “AON ‘390 ‘ydog | qysn8ny | “Ane ‘oune “AUT ‘judy | ‘yore ‘qoq “uBr "IVoX ‘savo X AJUOMT, LOF YUOT/L outes oY} Jo osedoay OY} pure YYUOTT Yow jo amyeitoduoay, UOT, 94} WoIMJoq VDUAOICT *[] @TaV yy, SUSPENSION OF A BALL BY A JET OF WATER. 279 XXIII. On the Suspension of a Ball by a Jet of Water. By Ossorne Reynoxps, M.A., Professor of Engineer- ing, Owens College, and Fellow of Queens’ College, Cambridge. Read March 8th, 1870. WHEN a ball made of cork, or any very light material, is placed in a concave basin, from the middle of which a jet of water rises to the height of four or five feet, the jet maintains the ball in suspension ; that is to say, it takes and keeps it out of the basin. The ball is not kept in one position, it oscillates up and down the jet; nor is its centre kept exactly mm a line with the jet, it often remains for a long time on one side of it. In fact, the ball appears to be in equilibrium when it is struck by the jet in a point about 45° below the horizontal circle. In this way, for some seconds at a time, the ball appears as though it were hanging to the jet, and then oscillates in an irregular manner about this position. If its oscillations become so great that it leaves the jet, it instantly drops, but in de- scending it generally comes back into the jet before it reaches the basin. The friction of the water causes the ball to spin rapidly ; and as it moves about the jet, it spins sometimes in one direction, sometimes in another, always about a horizontal axis. Of the water which strikes the ball, part is immediately splashed off in all directions, part is deflected off at the tangent, and part adheres to the ball, and is carried round with it, until it is thrown off by cen- trifugal force. The only explanations of this that appear to have been offered are based on one or the otherof thefollowing assump- tions, viz. that the centre of gravity of the ball remains directly over the jet, or that the jet is accompanied by a current of air which tends to carry the ball into it. With 280 PROF. 0. REYNULDS ON THE SUSPENSION respect to these assumptions, the fact that the ball will come back again into the jet when driven entirely away from it must upset the truth of the first, and at the same time it appears to establish the truth of the second. How- ever, some experiments, which will be subsequently de- scribed, made with a view to ascertain if this current exists, show that it does not. Besides which, Mr. Routledge and Mr. Wild have made some experiments. The former found that when the jet, directed horizontally to avoid the influ- ence of the falling drops, was brought very near to a light ball suspended by a thread, the ball showed no tendency to move towards the jet; and Mr. Wild settled the point by showing that the action of the ball is the same ina vacuum as it is in air. It appears, then, that neither of these assumptions is satisfactory. Now, of the forces which act on the ball, its weight acts at its centre in a vertical line, and is the only force which is not due to the action of the water. When the jet strikes the ball directly underneath, it will produce a force acting upwards in a vertical line, the magnitude of which depends on the height, and may therefore balance the weight of the ball. In this position the ball is, by the action of these two forces, in equilibrium, in the same manner as if it were balanced on a point. The slightest deviation in the jet will upset it; and then the jet will strike it on one side of the vertical line through its centre: when so struck, the forces at the point of contact may be resolved into two, of which one acts along the normal to the surface, or through the centre of the ball, and is due to the impulsive action of the water (this is called P), and another in the tangent plane at the point of contact (p) (this is due to the friction of the water, and is called R). If W be the weight of the ball, then P, R, and W are the only forces which at first sight appear to exist; and the question is, can the ball be in equilibrium under the action of P,R, and W? This question OF A BALL BY A JET OF WATER. 281 is easily answered ; for these forces are necessarily in the same plane; but they do not all pass through the same point, and, therefore they are not in equilibrium. To balance these forces, then, there must be some other force acting on the ball in the same plane with them, and which does not pass through p, or the centre of the ball. Now, besides the water which leaves the ball at p, there is the water which adheres to the ball until thrown off by centri- fugal force ; and to this we must look for the required force. The effect of a drop adhering to the ball will be very complex, being due to its weight, centrifugal force, and friction. However, if we neglect the weight as being very small, and therefore only able to increase slightly the weight of the ball, and to shift the point at which it acts a little way from the centre, the forces which the drop will produce may be stated accurately. For whenever a drop whose weight is w (lbs.) comes on to the ball with a velocity v (feet per second), and leaves with a velocity u, its whole effect, minus that of its weight while it is on the ball, is equivalent to a force a (lbs.) acting for one second in the direction in which the drop was moving and at the point at which it comes on to the ball, and a force at the point at which it leaves andina direction opposite to that im which it flies off. The first of these forces will form part of P and R; and therefore, besides the forces at the point P, the effect of any adhering drop will be equivalent to a reaction such as would be produced if the force neces- sary to throw the drop from the ball were concentrated at the point at which it leaves. If several drops be leaving the ball at the same time, the several reactions will have a single resultant, which will not pass through p, or the centre, unless they should be distributed equally all round the ball, in which case the reactions would simply produce 282 PROF. O. REYNOLDS ON THE SUSPENSION a couple on the ball, and would not have a single resultant. If the drops are not leaving equally all round, the resultant will act in a direction opposite that to in which the greatest number fly off. If, then, more water is thrown off in one direction than in another, and this direction is the same as that of the resultant of the three forces P, R, and W, this water will produce a force such as it has been shown must exist. First, then, is there any reason why more water should be thrown off im one direction than in another ? and, second, in what direction will that be? The water comes on to the ball at p, and that which adheres is at first spread out in the form of a thin film, on which centrifugal force immediately acts to collect it at the equator. As it collects at the equator, the adhesion becomes less, compared with the mass of water, and the drops separate themselves and fly off; in this way the water would begin to leave at p, and go on until it was all thrown off, so that much more water would leave above p than below. But, besides this, the weight of the water will tend to keep it on or to throw it off, and its action to keep it on will be greatest up to the top, after which the conditions for its leaving become more favourable; so that the water may begin to leave at p, or not till it has passed over the top of the ball ; but in either case most of the water will be thrown off before it gets below the horizontal circle on the opposite side to p. On examining the ball, it appears that the water begins to leave at the top. But in either case by far the greater part of the water files away from the jet. It was the discovery of this fact which has enabled me to explain the phenomenon; for this water causes a resultant reaction, which is the additional force necessary to maintain the equilibrium of the ball. Let this resultant reaction be called Q: it will act to- wards the jet, and its effect will be, first, to force the ball into the jet, and so will help to counteract the obliquity OF A BALL BY A JET OF WATER. 283 of P; secondly, it will assist in supporting the ball; and, thirdly, since it opposes the rotation, it will balance the tangential force R, caused,by the friction at p; and, pro- vided it have the proper magnitude, together with the forces P, R, and W, it is all that is requisite to explain the equilibrium. It remains to explain the fact, that the ball will fall back again into the jet after it has been driven out of it. This may be done; for the force P which forces the ball out, ceases as soon as contact ceases; but not so with Q, which drives the ball back again towards the jet ; for there will still be some water to be thrown off, so that perhaps for half a revolution Q will continue undiminished, and so bring the ball back again into the jet. Pos1TIOoN oF KQUILIBRIUM. With respect to the position of the ball when in equi- librium, nothing very definite can be established, as there are no known laws of adhesion; but it may be shown by general reasoning, that there are limits between which the point p must be, so that there may be equilibrium. Let the point p be at a fixed height, and let P equal the full force of the jet at this height when acting on the bottom of the ball or on a perpendicular plane. Then, if a be the angle which the normal at p makes with the vertical, P=? casia; and the horizontal component ! ! poy: P sin a=—2 sin a cos a= > sin2a; therefore Ul P Psin ee and is a maximum when a=45°, and Psina=o when a=0 or a=go’; 284: PROF. O. REYNOLDS ON THE SUSPENSION so that the tendency of the jet to force the ball to one side Ui increases from nothing to = as p moves from the bottom to a point at which the normal makes an angle of 45° with the vertical, and then decreases to nothing as p moves to the middle of the ball. The force Q may be fairly assumed to increase as the speed of rotation increases ; and this will be as the point of contact moves from the bottom to the middle of the ball. In the same way the force R, which will necessarily in- crease as Q increases, will increase as p moves from the bottom to the middle of the ball; and its horizontal com- ponent will follow nearly the same law as that of P. Considering, then, the horizontal forces only, there must be some position for p in which the horizontal component of Q and R will be equal to that of P; and if a horizontal circle be drawn through this point, it will limit the part of the ball in which equilibrium is possible. For any deviation without this circle the equilibrium will be stable ; z.e. if the centre of the.ball gets so far from the jet that the ball is struck in some point without this circle, it will come back again. As to the nature of the equilibrium for any deviation within this circle, I cannot speak positively ; but it is probably nearly neutral all over the enclosed area. ‘This seems to agree very well with the fact that the ball is in equilibrium when struck 45° below its horizontal circle and oscillates about this position. The following is a description of some experiments. The object was to ascertain :—first, whether or not air is the me- dium by which the water acts on the ball; secondly, how far the horizontal equilbrium of the ball depends on its rotation; and, thirdly, what is the exact position of the point in which the ball must be struck so as to be in equi librium, and, moreover, what is the nature of the equi- librium. OF A BALL BY A JET OF WATER. 285 The apparatus employed in these experiments consisted of a wheel three inches in diameter and half an inch broad at the rim, made of painted wood, capable of turning very freely about its axis, and suspended by two wires, with its axis horizontal, so that it could swing likea pendulum. A vertical jet of water was so arranged that it could be made to strike the reel at any point from below, or to miss it altogether. This was done by bringing the jet out of a horizontal pipe which would slide backwards and forwards in the same direction as the wheel could swing. This pipe was furnished with a cock, so that the force of the jet might be altered. Tn experiment No. 1, the pipe from which the jet issued was pushed so forward that the jet missed the reel by about an inch, and the jet was turned on to rise about six feet above the reel; the pipe was then brought back until the water passed as near as possible to the reel without touching it—but there was no apparent effect produced on the reel. The tap was turned so as to increase and then diminish the height to which the jet rose—still, with- out any effect. Experiment No. 2 was made with the same apparatus as No. 1. The reel was then changed for one six inches in diameter, and the same experiment repeated. The jet was placed so that it missed the reel (when hanging freely) by about two inches, and the water was turned on to rise about six feet. The reel was then pushed forward until it touched the jet and then let go; it imme- diately began to turn about its axis, but left the jet, swing- ing backwards and forwards, touching the jet each time, and each time gaining in speed of rotation. This went on for several oscillations; but as it got to turn faster, it ap- 286 SUSPENSION OF A BALL BY A JET OF WATER. . peared to stick to the jet for an instant before letting go; and having done this once or twice, it stuck to the jet alto- gether, and remained in contact with it, spinning rapidly. The experiment was then repeated with the jet at different distances, and with the larger wheel; the result was the same in all cases. I found it possible, however, either to increase or to diminish the force of the jet enough to pre- vent the reel from remaining in contact with it. The limits were about 2 and 8 feet. In experiment No. 3, the position of the reel when free was carefully marked, so that the least alteration could be noticed, and the jet was placed directly under its centre. In this position the jet did not cause the reel to move to either side in particular, but to oscillate backwards and for- wards. The jet was then pushed slowly forwards, and the motion of the ball watched. At first it moved away from the jet slightly, and remained away until it was struck about 60° from its lowest point, after which it gradually . came back to its initial position, which it reached when struck about 65° from its lowest point. The forward motion of the jet being continued, the ball began to follow the jet, the pomt im which it was struck moving upwards very slowly. When the reel finally fell from the jet and came back into its initial position, the jet missed it by about 24 inches. During the experiment the force of the jet was altered ; but within moderate limits this did not affect the position of equilibrium. This clearly shows that the position of equilibrium is about 25° from the horizontal circle, and for any deviation below this the equilibrium is much more nearly neutral than for any deviation above it. ON THE WATER OF THE IRISH SEA. 287 XXIV. On the Composition of the Water of the Irish Sea. By T. E. Tuorrs, Pu.D., and E. H. Morton. Read March 22nd, 1870. THanks to the investigations of Forchhammer, Von Bibra, Bischof, and others, our knowledge concerning the nature and distribution of the saline constituents of sea-water, and of the causes of the variations in its composition as observed in various parts of the world, is tolerably exten- sive and precise. English chemists, however, have con- tributed next to nothing to the general stock of our in- formation on this subject. This is not a little remarkable, especially when we consider the peculiarly favourable con- dition in which this country is placed for researches of this kind, by reason of its insular position. A few observations by John Davy, made in the course of his long voyages, two memoirs by Marcet in the ‘ Philosophical Transac- tions’ for 1819 and 1822, on the temperature and saltness of various seas, and an elaborate analysis by Schweitzer of the water of the English Channel, made in 1838%*, con- stitute by far the chief portion of the work done in this direction by English chemists. The chemical history of the sea is mainly to be derived from the researches and observations of chemists, principally French and German, the majority of whom were located at considerable dis- tances from the sea-board, and who laboured, therefore, under all the disadvantages which this circumstance neces- sarily entails. So far as we can learn, the water of the Irish Channel has never been analyzed. We have been induced, there- * Phil. Mag. xv. 1839. 288 MESSRS. THORPE AND MORTON ON THE fore, to undertake its analysis, in the hope of supplying information respecting the nature and extent of the modi- fications effected in the composition of sea-water by its proximity to our coasts. Accordingly Captain Temple, of the ‘Bahama Bank,’ light-ship, kindly collected for us a quantity of the water in the immediate neighbourhood of his vessel. The vessel is situated in lat. 54° 21'N., and long. 4° 11' W., seven miles W.N.W. of Ramsey, Isle of Man, and is placed nearly equidistant from the shores of Eng- land, Scotland, and Ireland. During the greater part of the day a strong current setting in from the south, pro- bably from the Atlantic, flows past the ship into the North Channel, and thence again into the ocean. The water, therefore, taken for analysis, was originally that of the deep ocean, which had traversed almost the entire length of the Irish Channel, and had consequently been ex- posed to all the influences due to the neighbouring sea- board, and to the influx of the numerous rivers along the coasts. The water was obtained in the early part of January 1870. The meteorological conditions at the time of collec- tion, and for some time previously, were in no wise re- markable. The analysis was commenced immediately on receipt of the water. Its specific gravity, compared with distilled water, free from air, and possessing the same temperature, was found to be DM te ea. © i lee ad a EA ne RE 102721 BG OMG. Wea smest chee ee eee 1°02484 These numbers differ but slightly from that usually ac- cepted as representing the mean specific gravity of the water of the ocean. The water of the Atlantic, according to Von Horner, possesses the specific gravity 1°02875 at o°; that of the English Channel at 15°°5 was found by WATER OF THE IRISH SEA. 289 Schweitzer to be 1:0271; on nearing the land the specific gravity fell to 1°0268. The following substances are stated by Forchhammer to exist in sea-water* :— Acids, or elements replacing them: Sulphuric, carbonic, phosphoric, silicic, boracic, nitric, arsenic, bromine, chlo- rine, iodine, fluorine. Bases: Sodium, potassium, magnesium, lithium, cesium, rubidium, ammonia, strontium, barium, iron, manganese, aluminium, zine, cobalt, nickel, lead, copper, and silver. In addition to these are variable quantities of organic matter, concerning the true nature of which we know as yet absolutely nothing. Dr. Angus Smith and Mr. Hunter, however, have already applied the permanganate reac- tion to determine the amount of this organic matter. None of the peculiar organic substances, such as crenic and apo- crenic acids, butyric, acetic, propionic, and formic acids, discovered in several mineral waters on the Continent, have been detected in sea-water. Of the thirty-one elements occurring in sea-water, the quantitative determination of nine or ten is alone possible. These are sodium, magne- sium, potassium, calcium, iron, chlorine, bromine, and sul- phuric and carbonic acids. We have further attempted to estimate the amount of nitric acid and ammonia. The remaining constituents have either been detected in the ashes of sea-plants and animals, whence their existence in sea-water has been inferred, or, as in the case of phosphoric acid and fluorine, they have been found in the boiler-de- posits of sea-going steamers. I. Estimation of the Total Solid Contents. The weighed quantity of water was evaporated to dry- ness in a platinum crucible, and the dried mass exposed to * Proc. Royal Soc. xii. p. 130, 1862. SER. III. VOL. IV. U 290 MESSRS. THORPE AND MORTON ON THE a temperature of about 180° C., until its weight appeared to be constant. Sea-water contains a notable quantity of magnesium chloride, which decomposes during the pro- cess of drying, evolving hydrochloric acid. This source of error was easily obviated by adding, as recommended by Mohr, a small known quantity of recently ignited sodium carbonate to the water, when the magnesium chloride is converted into the more stable carbonate. Amount in 1000 Water taken. Residue obtained. grams of water. grams. grams. grams. TL. oa Sr 85 G4: 1°7309 33°8360 II. ... 50°7608 1°7178 338411 Mean: 508 2.08352 33°83855 According to Forchhammer, the amount of the total saline constituents of the water of the northern portion of the Atlantic, between the parallels 30° N. lat. and a line from the north of Scotland to the north of Newfoundland, is subject to very slight variation: the mean quantity amounts to 35'°976 grams per 1000. It is therefore evi- dent from the above result, that the relative amount of solid matter contained in sea-water is perceptibly dimin- ished in the neighbourhood of coasts; and this in the case of the Irish Channel can only arise from the admixture of fresh water flowing down in the form of rivers from the land. This conclusion is fully borne out by the older analyses of Clemm, Figuier and Mialhe, and Bischof, of the water of the German Ocean, collected in the neighbour- hood of the coasts. In no case did the amount of saline constituents exceed 33 grams per 1000. (Min. 30°5, max. 32'8.) WATER OF THE IRISH SEA. 291 II. Estimation of the Sulphuric Acid, as Barium Sulphate. Waiter taken. BaSO, obtained. SO, in 1000 grams. grams. TS 2... 102°272 0°6447 2°5972 TY ....2. 460°206 0°6295 25884 NECAW 2255, +5 2°5928 In the older analyses, the sulphuric acid was calculated as SO,: the above number reduced to the amount corre- sponding to this formula is 2:16075. Probably no con- stituent of sea-water is subject to greater variations in amount than the sulphuric acid. This may be due to several causes, among which may be enumerated (1) the varying amounts of sulphates brought down by rivers, and (2) the fact that the sulphuric acid contained in sea-water is frequently reduced in the presence of organic matter to sulphuretted hydrogen*. The variation in the Atlantic, ac- cording to Forchhammer, may amount to 0°0145 per cent. (max. 0°2436 per cent., min. 0'2289 percent.). The mini- mum quantity, it will be observed, somewhat exceeds that found in the water of the Irish Channel, again showing the influence of the influx of fresh water from the rivers. The water of the English Channel, according to Bischof, contains a similar amount of SO,, viz. 02141 per cent., with which our result agrees perfectly. III. Determination of the Total Amount of Lime. We found some little difficulty at the outset in exactly determining the proportion of this constituent by the ordi- nary method of separation, owing to the facility with which varying quantities of magnesia coprecipitate with the cal- cium oxalate. By repeatedly dissolving the mixed oxalates in hydrochloric acid, and reprecipitating the calcium salt by the addition of ammonia and a few drops of ammonium oxalate, we at length obtained it perfectly free from ad- * See Hayes, Sillim. Americ. Journ. March 18651, p. 241. uz 292 MESSRS. THORPE AND MORTON ON THE mixed magnesium oxalate. The precipitate was collected, dried, ignited, and weighed as caustic lime. Amount in Water taken. CaO obtained. 1000 grms. | ee ioc i tet 0'0878 057466 DY 0598535928 0'0883 0°57589 IIT. ... 153°266 00881 0°57482 Mean. 2. 22 0.38: 0°57512 The amount of lime contained in the water of the Irish Channel is somewhat less than that usually found in the Atlantic Ocean,—according to Forchhammer 0°05g7 per cent. IV. Estimation of the Magnesia, determined in the filtrates obtained in the foregoing estimations. Water taken. P. MgO in 1000 grms. L bapa hha ges 0°8649 2°03275 L,. 2.053266 08642 2°03 192 Meats. sso. tsar 2°03233 According to the authority already quoted, the amount of magnesia -contained in the water of the ocean far distant from land varies about 0°0093 per cent. ; max. 0°2209 per cent., min. 0°2116 per cent. V. Estimation of the Caletum Carbonate. The lime contained in sea-water exists as sulphate and as carbonate, the latter salt beg dissolved in an excess of free carbonic acid. On boiling the water the gas escapes, when the calcium carbonate separates out. Its amount was determined by boiling a weighed quantity of water for about an hour, taking care to add distilled water from time to time in order to prevent the precipitation of the cal- cium sulphate. The water on cooling was again weighed, divided into two portions, and filtered through dry filters ; WATER OF THE IRISH SEA. 293 by again weighing the filtrate, the amount of the original water employed in the several determinations was easily calculated. The lime in solution was then precipitated as oxalate, with the precaution indicated in the preceding paragraph. CaO in Water taken. CaO obtained. 1000 grms. i. i. 205°860 O*1130 0°54892 LEMS. 214020 O'1173 0°54808 Moan 052.602. 55< 0°54850 The total quantity of lime contained in the water of the Irish Channel amounted, according to the determina- tions contained in Section III., to 0°57512 gram per 1000. On subtracting from this the amount contained in 1000 grams of the boiled water existing in combination with sulphuric acid, the quantity of lime remaining amounts to ‘02662 grm., equivalent to ‘04754 calcium carbonate per 1000 grms. of water. The washed calcium carbonate con- tained a mere trace of magnesium carbonate. This amount of calcium carbonate, although agreeing with the older de- terminations of Bischof and Schweitzer, made on the water of the English Channel, is in all probability too low, on account of the solubility of the carbonate in solution of the alkaline chlorides. No sufficient data exist for sup- plying the proper correction to this result. According to John Davy, only in the vicinity of coasts does sea-water contain calcium carbonate. Inthe water of the ocean, far away from land, he failed to detect even a trace; and in the numerous analyses made by Von Bibra on specimens collected in various parts of the world, no mention is made of this ingredient. VI. Estimation of the Total Amount of Alkaline Chlorides. To the weighed portion of water was added a small quantity of barium chloride, in order to separate the sul- 294 MESSRS. THORPE AND MORTON ON THE phuric acid; the magnesia, together with the excess of the barium salt, was removed by boiling the solution with milk of lime in a silver dish. The water was then filtered, and the lime in solution precipitated by ammonium car- bonate, and oxalate. On again filtering, adding a small quantity of hydrochloric acid, and evaporating to complete dryness, a minute amount of silica was rendered insoluble, together with the traces of magnesia which had escaped previous separation. This process was repeated until the chloride dissolved to a perfectly clear solution. The dried mass was then heated to dull redness, until it ceased to lose weight. Mixed chlorides Amount in Water taken. obtained. 1000 grams. §7°1062 1°3875 27°15000 57°1440 13920 27°21725 Mean 2.-c5- 2.226 27°18363 In the foregoing process no account has been taken of the minute quantity of lithia present in sea-water, the whole of which would probably be contained in the mixed chlorides—partly in the state of chloride, partly in that of oxide. Although the presence of this substance in sea- -water may easily be demonstrated by means of the spec- troscope, a few decigrams of the solid residue amply sufficing for its detection, its quantitative determination has hitherto not been attempted, more probably on ac- count of the imperfect nature of the methods employed in its separation than of the relatively minute quantity contained in the water. Indeed it is almost certain that the proportion of this element exceeds that of the ammonia or nitric acid, silica, or oxide of iron, the amounts of which substances in sea-water may be ascertained with some degree of precision. WATER OF THE IRISH SEA. 295 VII. Determination of the Potash and Soda contained in the mixed Chlorides. Probably none of the processes employed in the analysis of sea-water is so unsatisfactory as that generally used in the determination of the amount of sodium and potassium. The quantity of the latter element contained in sea-water is relatively very small; and the loss of potash in the ordi- nary method of separation, as the platinum salt, amounts, even under the most favourable circumstances, to upwards of one per cent. The difficulty in applying this method for this purpose has already been pointed out by Usiglio* in his “ Memoir on the Composition of the Water of the Mediterranean.” We have preferred, therefore, to deter- mine the proportion of potash and soda contained in the mixed chlorides by the indirect method of estimating the amount of chlorine present in the mixture, and calcu- lating from this the proportion of the two alkalies. This manner of proceeding is certainly more expeditious, and, we believe, if conducted with due care, quite as accurate as the other method. Mixed Ag(Cl In 1000 grms. chlorides. obtained. NaCl. KCl. Na. x. E> ... 269875 3°3348 1°3492 0°0383 10°3890 *39300 if <2. i°g9920 3°3957 1°3540 0°0380 10°4150 38963 Means .......... 104020 0°39131 VIII. Determination of the Bromine. When silver nitrate is added to a cold solution of the alkaline bromides and chlorides, in quantity insufficient to precipitate the whole of the halogens, and the mixture of the silver salts allowed to remain in contact with the liquid for a few days, the whole of the bromine is removed from the solution, and is contained in the precipitate as silver bromide. Upon this principle is based the method * Ann. de Chimie, ser. 3. xxvil. 104. 296 MESSRS. THORPE AND MORTON ON THE which we have employed in the determination of the amount of bromine contained in the water of the Irish Sea. This method has been carefully studied by Fehling, and we have therefore followed the directions given by that chemist in his memoir*. To the measured quantity of sea-water, in each case a litre, weighing 1027 grms., a small quantity of solution of silver nitrate was added (about = of that re- quired to effect complete precipitation), and the liquid re- peatedly shaken for eight days. The precipitates were then collected, thoroughly washed, dried, and weighed. Water taken. Amount of mixed grms. silver salts. UL esyenase: 1027 2°85068 1 Aan eae 1027 2°31020 The mixed silver salts were then transferred to porcelain boats, and heated in a stream of pure hydrogen until they ceased to lose weight. All the weighings were made by the method of vibrations, as described by Bunsent. By this means a difference of one-hundredth of a milligram is easily detected. Amount of AgCl Ag Equivalent to On the original and AgBr taken. _ obtained. AgCl. amount. germs. grm. grms. grms. 3°39584 178195 2°36790 281736 2°11510 1°56640 2°08148 2°27347 Hence the amount of AgBr is Bromine in 1000 grms. Ts pats eaietss OTAODG' +s. Ah. sea 0°05827 TD. Sided DUG GOW td. eeecue. ceaeee 006438 Mian \scecvcsec <2 0°06133 The presence of iodine in sea-water has not been con- clusivety demonstrated. Its existence in the water has simply been inferred from the fact of its being contained in * Journ. f. prakt. Chem. xlv. 269. t Phil. Mag. 1867, xxxiv. WATER OF THE IRISH SEA. 297 various fucoid plants. About 100 grms. of the dried re- sidue of the water of the Irish Channel, evaporated with sodium carbonate, were digested with absolute alcohol for some days, the solution evaporated to dryness, and the solid matter again treated with absolute alcohol, filtered, and a second time evaporated to dryness. The dried salt was then dissolved in a few drops of water, a small quantity of clear starch paste added, together with two drops of a solution of nitrogen teroxide in sulphuric acid. Not the slightest coloration was perceptible. Assuming, with Stromeyer, that zsoooo part of iodine may be thus detected, and assuming, further, that the delicacy of the reaction is not interfered with by the presence of bromides or chlorides, it follows that the amount of iodine contained in sea-water cannot exceed I part in 100,000,000 of water, and is probably much less. IX. Determination of the joint amount of Chlorine and Bromine, by precipitation as Silver Salts. Water taken. Silver salt Containing Cl per 1000 grms. obtained. Ag(Cl. grms. i 336.425-65.10 1°9319 1°9283 18°6182 if 5 256306 1°9352 1°9315 18°6348 Mga f25 coupes: 18°6265 X. Estimation of the Ammonia. 5237°7 grms. of the sea-water were boiled with a quantity of pure caustic soda (made from metal) in a distilling-apparatus until about two litres had passed over; this was a second time distilled through a good condensing-arrangement. The second distillate, contain- ing all the ammonia, weighed 365°78. The greatest care was taken in the operation to prevent the solution absorb- ing ammonia from the atmosphere of the laboratory ; and the vessels employed were perfectly clean and new. The 298 MESSRS. THORPE AND MORTON ON THE ammonia in solution was then estimated by Nessler’s method. One cubic centimetre of the solution of am- monium sulphate employed in the comparison was equiva- lent to o‘ooo10 of nitrogen. The amount of this solution required to give a tint equal to that afforded by 50 cubic centimetres of the distillate was (1) 6:2, (2) 6°9, (3) 6:2; mean, 6°4. Hence the ammonia in 1000 grms of water =o'o000108. ao XI. Estimation of the Nitric Acid. The liquid remaining in the retort was carefully decanted, when clear, from the precipitate formed on adding the caustic soda solution; this precipitate was repeatedly washed, and the washings added to the main bulk of the solution. The entire quantity of the solution was then concentrated until about 20 cub. cent. only of liquid re- mained ; this was filtered into a small flask ; a large excess of pure caustic soda was then added, and the solution was boiled for about an hour, in order to remove completely any traces of ammonia which might have been absorbed from the air of the laboratory. When cold, two compound helices of zinc and iron were thrown into the solution, which was further treated according to the method of Vernon Harcourt. The ammonia contained in the distil- late, derived from the action of the nascent hydrogen on the nitrate in solution, was estimated by Nessler’s method. The weight of the distillate was 96°3 grms. One cubic cen- timetre of the ammoniacal solution used for comparison was equivalent to o‘o00112 NO,H. The amount of this solu- tion required to afford a tint equal to that caused by 25 cub. cents. of the distillate was (1) 19°0, (2) 17°8, (3) 20°2; mean, 190 cub. cent. Hence the amount of nitric acid contained in 1000 grms. of sea-water is 0°001563 gym. E The ammonia and nitric acid contained in sea-water are WATER OF THE IRISH SEA. 299 doubtless produced by the decomposition of nitrogenous organic matter. Now, since this process of decomposition is continually going on to an enormous extent on the sur- face of the earth, we should naturally expect to find far more ammonia and nitric acid in sea-water than analysis shows to be actually present. The amount of the substances thus formed on the earth must be very large; but the quantity carried down to the sea by the rivers is exceed- ingly minute: we are acquainted with at least fifty ana- lyses of rivers flowing’ directly into the sea; but in none does the proportion of nitrate exceed 1 part in 100,000 of water, even when the river receives the sewage matter of large towns. This remarkable disappearance of nitrate and ammoniacal salts is undoubtedly to be traced to the peculiar absorptive power of soils for salts containing ni- trogen in a form available for the nourishment of plants. Way has shown that nitrates and ammoniacal salts are completely removed from solution on filtration through a layer of soil. XII. Estimation of the Iron. The precipitate formed in the retort on adding the caustic soda to the sea-water was assumed to contain the whole of the iron as ferric oxide. This precipitate was dissolved in dilute sulphuric acid, the iron reduced by means of zinc, and its amount estimated by a permanganate solution, of which one cubic centimetre was equivalent to 0°00106 of oxygen. Amount of Fe,O, found in 1000 grms. =0'00465. The following synoptical Table shows the mean results _ of the foregoing determination: the numbers express the amount of the various ingredients in 1000 grms. of the sea-water :— 300 MESSRS. THORPE AND MORTON ON THE n/Ghiomne te) panstohats. ath theca 18°62650 Bs APOIO: | oi... ai'ussaeen semaine ssemeee "06133 3; Nulphuric Acid (SO, ) crac ascueacssoees 2°59280 4. shinie (total) Hee. Ee ty ht i) §. Calcium carbonate, 00 $.2:-.c. x2 ices nctecc aneeueanenes a2 1°33158 Caleiumcarbouatewacca..a-sesetdatee ane 04.754 Listhinm chlorides. 3,25: vawe-ccesqattonc nee traces. Ammonium: chloride 7.22. wcsese' ss desnaewe "00044 Magnesium: nitrates. ..i ced te occtou-se ste one "00207 Silicic:- acid: tonesesatete entree: sate traces. Ferrous: carvOmate”..¢..--ce-aness reactant tees 00503 33°85946 Amount directly determined...... 33°83855 The water employed in the foregoing analysis was col- lected in mid-winter ; it becomes interesting to know if its composition is uniform during the various seasons of the year. Fortunately we can offer some evidence on this point. In August 1865, after a continuance of exception- ably fine weather, one of us collected some sea-water in the neighbourhood of the Bahama-Bank Light-ship, and determined the total quantity of its saline constituents, together with the amount of chlorine and sulphuric acid. WATER OF THE IRISH SEA. 301 I. Total solid contents. Water taken. Residue Amount per grms. obtained. 1000 grms. Tt... 46°9516 1°6026 34°1330 TY, hic. 94°9920 1°1704 34°0312 | ne Se 34°0821 II. Determination of Sulphuric Acid. Water taken. BaSO, SO, in grms. obtained. 1000 grms. Es. 58213 G°32.95 26347. Hye 57°F 20 0°3242 2°6130 Whee 3, ci sie-6s 2°6239 Equivalent to 2°1870 SQ,. III. Determination of Chlorine. Mixed salts Clin Water taken. obtained. AgCl. 1000 grms. fi. 51°5700 3°8862 3°8788 13°7344 MASI) Gr 567 3°8353 3°8780 18°7376 TE 2.) §1"0848 3°8790 3°3718 18°7340 Miegn seas. ssc.e: 13°7353 Hence we see that the proportion of solid matter con- tained in the water of the Irish Sea is somewhat greater in summer than in winter, the variation amounting to 0°0144 per cent. It is also conclusively proved that the relative amount of saline constituents present in the water of the Irish Channel is invariably less than that contained in the water of the Atlantic Ocean lying between the same parallels. According to Forchhammer, the mean proportion of the leading constituents of the water of the Atlantic, far away from the shores, is as follows :— CL =| 680,. | Cad. | MgO. | Total salts. a | es Se | Absolute amount per 1000 pa 19°865 | 2°362 | 07588 | 2°199 35°976 Relative amount ... 100 | 11°89 2°96 I1'07 I8I‘10 302 ON THE WATER OF THE IRISH SEA. Arranged in this manner, our determinations on the water of the Irish Sea give the following proportions :— Cl. SO, CaO. | MgO. | Total salts. Absolute amount | Summer] 18°735 Oy Bae a SA aa: Maer re 34°082 per 1000 { Winter..| 18°627 2161 0°575 2032 33°3838 prms. ... Relative Summer TOO: WEES P Me Secmael My Te ates 181'g1 amount. Winter.. 100 | 11°63 3°09 10°93 182709 We have not attempted to determine the amount and nature of the gases dissolved in the water of the Irish Sea. When compared with the amount dissolved in river-water, the quantity of the gases contained in sea-water is exceed- ingly small. It would be interesting to determine the proportion contained m mixtures of fresh and sea-water at the mouths of rivers. Taking Mr. Hunter’s researches on the composition of the gases dissolved in normal sea- water as the basis of the comparison*, we should thus be in a position to judge of the influence of the river-water in this particular direction. * Journ. Chem. Soc. MR. J. BAXENDELL ON THE RATE OF MORTALITY. 308 XXV. On the Influence of Changes in the Character of the Seasons upon the Rate of Mortality. By Josuru BaxENDELL, F.R.A.S. Read April sth, 1870. In the summer of last year, I undertook a discussion of the Rainfall observations made at the stations of the Man- chester Corporation Water-works during the 14 years 1855-1868 ; and among the results obtained I found that although the total amount of rainfall in different years appeared to be governed by no regular law, yet the pro- portional amounts in the different seasons, during the eight years 1855-62, exhibited a marked contrast to those in the six years 1863-68, the amounts in the spring and summer months exceeding those in the autumn and winter months during the former period, while in the latter the autumn and winter amounts exceeded those of spring and summer. The results for the central station, Arnfield, are as follows :— Total fall of rain Total fall of rain during the spring during the autumn and summer months. and winter months. Difference. inches. inches. 7G Rae ae ke pes ee he Foe 7 Oa ies: Sanat + 4°09 Ns Sh a nee BEIOR i 2 Had Midas oat 7H i: Pe RMR EE A ea — O45 SG ae ee De dee, | ae EP OPE ES Se 7 Ee SRO A + 815 BA BOL scoters socks AO aneme ie: bacrinedige RG FOr er cete ses catetened + 3°18 10 I Sea QAM cater PA dates 3 MOTTA Res. grectauach te: + 072 MGOs Sad cs wvip caine BANGOR Y, |. daly SoG elas + « shir BESO cies sabe resis cas: + 8:46 oS! eo Gee ieee ROe ner” be YG a Ra ee ae aren + 2°99 1862 ENS: «bee Re as eS Ae BP OS nesvacvaveds sscen + 3°63 FOOQ? wspecevdsnss a ie eR eee ee 2 et 0 SR ed RE — 7°45 Ne eae PRGA au gates staan s BOER ON stn ass caincyoamintin — 2°26 1865 4 ee). ee ee ee BGO wakancssaatunae eas — 2°41 EGOO (oss ccseges BOLTE We ctecsepevewcesios BOIGl: Lgtecnscaas -p« — 6°08 MSOF. soesoeer tect POId Bib. daniansigur tegen’ BOPP Saad ss siganesaest — 2°04 PI << dncdeedace BPE Rian ticc ue winic - PBL ON Sirians essen se —10°25 It will at once be seen that during the first eight years 304 MR.J. BARENDELL ON CHANGES IN THE SEASONS the differences, with one unimportant exception, have all the sign plus; while during the remaining six years they have all the sign minus. The average value of the differ- ences in the first eight years was + 3°84, and in the last six years —5'08 inches. The returns from the other stations of the Manchester Corporation Water-works exhibit similar results. It is evident, therefore, that at the end of 1862 a marked change took place in the character of the climate of this locality, the spring and summer seasons becoming much drier, and the autumn and winter months wetter, than they had been during the previous eight years. [ may add that this altered character of the seasons was continued through the last year, 1869, the total rainfall at Arnfield during the spring and summer months having been only 12°48 inches against 27°57 inches in the autumn and winter months, thus showing a difference of —15'09 inches. In considering the differences in the temperature, humi- dity, and pressure of the atmosphere, and in the direction and force of the wind, in the two periods, as indicated by this marked difference in the distribution of rainfall, ‘it seemed to me highly probable that corresponding differ- ences would exist in the state of the public health, and that the mean rate of mortality during one period would be sensibly different from that during the other. I therefore extracted from the annual Reports of the Registrar General the rates of mortality in Lancashire, Cheshire, and the West Riding of Yorkshire during the years included in the two periods, omitting the last year of the series, 1868, as the Report for that year has not yet been published. These rates are as follows :— AND THE RATE OF MORTALITY. 305 Annual rate of mortality per cent. in Lancashire. Cheshire. West Riding. ESES) jn eaccsoe BEGROl Ses esos EGY .cusccenes ses 2223 RSG Oe ce heest sas 2S ee ee BEOAR 5h leas aks 2292, | RR RS oe S2GSRt dient. B2OO Mt Weare. 2°368 BOGS tceternitcates BOGE" Saascshenta DDO T scuceos eevee 2°4Q1 BESO, 20s Morass. DAGA sve.cvecese BEGAN LS Sic. 2°396 BEGON dain vecarsns BARAT Govan sess a PUTAS Cee Sanat ae 2°360 CL i ee Bite PRI sewince asa PICORE a reaieaea dsc 2°321 | BAGOO™ a cnetceunes < SPA Maes siacseee 2°264 io ey ae me 2°62.) seacccnnrnioe CCS sae anon ne 2574 MEAD .ocet 00's OREM, cose sndn ess 2,300 2°656 BOSS aceon xones : SAD chan cns n