perhaps impossible to determine precisely; but it is probable that the former supposition is the more correct one.

DESCRIPTION OF PLATE IV.

In Tropaeolum the ovules are anatropal and pendulous, with the raphe next the placenta. It will be observed that all the objects figured are inverted, in order to let the organic apex of the germ be directed upwards. Figs. 1-5 are all drawn on one scale; figs. 6 and 7 on a much smaller one. Fig. 1. Section of young seed, with a very young bottle-shaped germ at the apex of the embryo-sac. pri, Primine; sec, Secundine; se, Embryo-sac; mic, Micropyle; a apex, c body, and b the pointed base of the germ. In this figure the form of the germ, and the cells of its neck and body, may be relied upon as being correctly indicated; but I am uncertain (as I have stated in the text) of the number of cells forming the pointed base. I am inclined to think, however, that two cells are to be seen on the side view as I have given them in the drawing.

Fig. 2. Section of young seed somewhat further advanced. The axis of the germ is now curved, and its apex is a little enlarged, forming the first indication of the "embryo," emb; the narrower portion below it becoming the suspensor, susp. On the outer side of the body of the germ is a small rounded enlargement, the rudiment of the extra-seminal process, esr. Se, b, c, and mic, as before.

Fig. 3. Young germ further advanced than that in fig. 2. Emb, susp, esr, and b, as before. From the increase in size of the extra-seminal process, the suspensor appears as if thrown to the side.

Fig. 4. Young germ still further advanced. The inner side of the body of the germ is now distinctly bulging. This protuberance is the first indication of the placental root (pr) The cellular structure is represented in this figure. The basal point (b) now consists of a single cell. The extra-seminal process (esr) has not yet perforated the seed-coats. Emb and susp as before.

Fig. 5. Young germ at the period when the extra-seminal root (esr) has just perforated the seed-coats. The placental process (pr) has become considerably enlarged, and is now conical and pointed. The cellular structure of the placental root and base of the germ is indicated, in order to show the amount of cell-multiplication which has occurred. Emb, susp, and b, as before.

Fig. 6. Portion of young germ at a later period. The conical and pointed placental process (pr) now tapers considerably at its extremity; its rootlike elongation is commencing. The suspensor has been broken off short. Lettering as before.

Fig. 7. Section of a portion of a young seed (s), and placenta (pl). The placental root (pr) is now considerably elongated, and has reached the placental vascular bundle (vb), along the inner side of which it already runs for a short distance. The extra-seminal root (esr) is much elongated, and is seen to perforate the seed-coats a little to the outer side of the micropyle (mic). Vascular bundle of the raphe, r. The young cotyledons are now distinctly visible on the embryo (emb). Susp, Suspensor.

263

On the Barometric Depression, and Accompanying Storm, of the 19th October 1862. By THOMAS H. CORE, PrivyCouncil Lecturer in Mathematics, Normal School, Edinburgh. (Plate V.)

*

The data on which the present paper is founded were obtained principally from the returns from the Society's stations, but from the following sources in addition: from the returns from the Northern Lighthouses, kindly furnished to me by Mr Thomas Stevenson; the log-books of various merchant ships, obtained from several shipowners in Leith; the files of the "Shipping and Mercantile Gazette," and "Mitchell's Maritime Register," in Leith Reading-room; and the Board of Trade Meteorological reports, published in each morning's "Times." As the 19th of October happened to be a Sunday, the observations connected with the storm are not so numerous and complete as I could have wished as regards England and Ireland; but this was partially remedied by a few special returns I obtained, some directly from private observers, and others from letters in the daily newspapers.

I shall first notice shortly the barometric fluctuations throughout the month of October, and then consider more particularly that of the 19th.

The monthly fluctuations are represented in Diagram I., in which are drawn the barometric curves for England, Ireland, and Scotland. For the first nine days of the month the barometer was considerably above the mean height, the weather was generally fair, some of the days being warm and pleasant, with bright hot sunshine, and there was comparatively little moisture in the air. From the 9th to the 12th the barometer sank continuously about an inch in Scotland, and four-fifths of an inch in England and Ireland, the thermometer being still high, and the air being nearly saturated with aqueous vapour. The moist and warm air being thus relieved of a considerable amount of barometric pressure expanded and cooled, and its moisture was consequently precipitated in the form of a dense fog, which was very prevalent for three or four days

* Read before the Scottish Meteorological Society on 14th January 1863.

over the whole country. From this time till the 16th a succession of fresh, and sometimes strong westerly breezes, accompanied by a slightly rising barometer, brought copious showers of rain, which had the effect of considerably cooling the air. From the 17th till the 24th the oscillations of the barometer were extensive and remarkable, the mercury falling in some places upwards of an inch in twelve hours. At the same time the weather was extremely unsettled, strong gales and sometimes even violent tempests, accompanied often with heavy rain, and at times with hail and lightning, blowing from S.W. to N.W. These storms were particularly violent on the afternoon of Friday the 17th, about midnight of Sunday the 19th, and on the evening of Wednesday the 22d, and more so in England and Ireland than in Scotland. Both in the storms of the 19th and the 22d, the pressure of the wind is recorded at many stations as being twenty-five lbs. on the square foot, which gives for its velocity the very unusual rate of seventy miles per hour. The newspapers were full of the details of the disastrous effects of these hurricanes, both on land and at sea. In London, innumerable sheds and chimney-stalks were blown down, many serious collisions took place on the Thames, by which some vessels were sunk and many quite disabled; and at high water the tide was forced over the banks, deluging many warehouses, and destroying a vast amount of property. In the Downs, where a large fleet was moored, several ships went down at their anchors; and at Shields, a whole fleet of colliers, which had put to sea in despite of a warning from Admiral Fitzroy, was dispersed, many of them foundered, and many were driven over to the coast of Norway. By the wreck and damage done to vessels belonging to the Tyne alone, the underwriters sustained a loss of L.40,000. On the West Coast, however, where the storm was blowing towards the land, the disasters were still more numerous, the whole shore being literally strewn with wrecks, both on the morning of the 20th and the evening of the 22d.

Nor was the violence of the storm confined to this country; it raged with almost equal severity over the north-western part of Europe, the Bay of Biscay, and far out in the Atlantic Ocean. At Antwerp the Queen was detained for six

days, being prevented from crossing by the boisterous state of the weather. The " Times" correspondent, writing from Paris on the 22d, says, "The hurricane, which has been blowing over Paris for the last three days, and which has not yet abated, caused much damage. The garden of the Tuileries is covered with broken branches of trees," &c., &c. "A letter from Cherbourg states, that a violent hurricane has prevailed in the Channel for some days past, the wind varying from S.W. to N.W. The harbour of Cherbourg, 'the hotel of the Channel,' as it was called by Vauban, is crowded with vessels seeking shelter from the storm." Again, from Havre: "The storm is still raging with unabated violence. On Sunday night, the wind shifting from S.W. to N.W., blew in heavy squalls. The sea rose to an unusual height, and showers of rain fell in rapid succession. On Monday the hurricane continued, but not with such extreme violence." The two screw steam-ships, "Ceylon" and " Tartar," were both crossing the Bay of Biscay on their voyage homeward to Southampton,-the former on the 19th, the latter on the 20th,-and both reported having met with heavy westerly gales, with a high sea and thick weather. Again, the barque "Balclutha" left Greenock for St John's, Newfoundland, on the 29th September, and had proceeded half-way across the Atlantic, when, on the 17th, she experienced such tempestuous weather, that she was considerably damaged, and obliged to put back. Her track is represented by the dotted line in Diagram IV. The following is a short extract from her log-book, which, as is customary at sea, is kept in nautical time, and is thus twelve hours in advance of civil time :

"Oct. 16th, N.W. by N.-Begins with hard gale and dark cloudy weather.

" 4 A.M., W.N.W.-Cloudy, with continual rain and heavy topping sea.

"8 A.M., W. by N.-Hard squall.

"17th, N.N.W. to N.W.-Begins with hard gale and darkening weather, accompanied by terrific squalls, and showers of hail, sleet, and snow.

"8 P.M.-Same wind and weather, with heavy topping sea;

ship labouring very much, and straining so much that the trembling of her whole frame could be distinctly felt on deck. Throughout midnight, furious gale with terrific squalls, and blinding showers of hail, sleet, and snow.

"3.50 A.M.-Gale raging furiously, with tremendous curling sea. About this time a sea broke aboard on the port-bow with terrific force, sweeping the deck fore and aft, and doing immense damage to the ship, and also carrying overboard two able seamen.

"Latter part.-Gale somewhat abated, but heavy sea still making a clean breach over her decks.

" 18th, N.W. throughout.-Commences with a continuation of heavy weather, with hard squalls and showers of rain. "Middle part.-More moderate squalls, not so violent, and sea abating.

"Latter part.-Still moderating.

19th, from N.W. to N.N.W. throughout.-Begins with fresh gale, accompanied with frequent squalls and showers of hail.

"Middle part.-Increasing gale with heavy squalls.

"Latter part.-Strong gale and high sea, with hard squalls and showers of hail."

The "Balclutha" now put back, and on her return voyage continued to experience very stormy weather.

What I have already said is sufficient to show that these storms, from the 17th to the 24th, were very violent, and felt over a wide area. From the 26th to the end of the month the weather was more moderate, with a steadily rising barometer and a low temperature, showers of sleet alternating with snow and rain.

The barometric range for October, or difference between the highest and lowest readings, amounted at many stations to more than two inches, which is 50 per cent. greater than the average range for October. The following table of the lowest barometric readings for each month of the year shows this fact in a different manner. The numbers in the first column are the means of the monthly minima for the five years 1857-1861 inclusive, for one selected station (Sandwick in the Orkney Islands); and those in the second column are