When first I began to attend to this Conjunction, I not only determined myself to watch diligently an appearance so important, but invited others also whom I knew to be interested in astronomy to do the same, in order that the testimony of many observers, should it so happen, might more firmly establish the truth; and especially because, if observations were made in different places, our expectations would be less likely to be frustrated by a cloudy sky or any other obstacle. I wrote therefore immediately to my most esteemed friend William Crabtree, a person who has few superiors in mathematical learning, inviting him to be present at this Uranian banquet, if the weather permitted; and my letter, which arrived in good time, found him ready to oblige me; he therefore carefully prepared for the observation, in a manner similar to that which has been mentioned. But the sky was very unfavorable, being obscured during the greater part of the day with thick clouds; and as he was unable to obtain a view of the Sun, he despaired of making an observation, and resolved to take no further trouble in the matter. But a little before sunset, namely about thirty five minutes past three, certainly between thirty and forty miuntes after three, the Sun bursting forth from behind the clouds, he at once began to observe, and was gratified by beholding the pleasing spectacle of Venus upon the Sun's disc.

With more than twenty horses and mules at day-break on the 14th of July, clattering on the flinty pavement, and with as many men shouting to their respective animals, and disputing among themselves for the lightest loads—there was no more sleep from that early hour, for any one in the inn.

Well did the muleteers understand the art of making fast on pack-saddles a large variety of goods. We distributed rope liberally amongst them, they twining it ingeniously over the burdens and around the bodies of the creatures; then taking a bend of it under the belly, they inserted a tough curved stick, and twisted ferociously, until every turn of the rope became perfectly taut; or the mule, as it falsely seemed, lifted almost bodily off his four legs, would have shrieked if he could, at the vehement stricture of all his internal organs.

Such of the men as had completed these arrangements, wanted to start off at once, and we had much difficulty in restraining them. Certain ideas, were in our mind, of keeping them altogether in the ascent of the mountain, overlooking their proceedings, and making a lightly loaded mule occasionally change burdens with one more heavily laden. We should not perhaps have made such strenuous attempts as we did towards this end, had we been fully aware of the utter impossibility of putting it in force throughout the whole day's journey; or had we been as well informed, as the experience of three months subsequently made us, of the honesty and perfect trustworthiness of these carriers.

On the morning of July the 15th, I rose by break of day to examine the mountain top, on which we had effected our lodgment in the dusk of the previous evening. The prevailing colour of everything about, was light yellow; the soil, something like a mixture of powdered clay and sand, plentifully strewed with blocks of trachyte. These exhibited generally some appearance of stratification; and the ground about them was thinly, or rather distantly, dotted with alternate bushes of codeso and retama; both of them very stunted, and oftener dead than alive.

So far, there was nothing very different in the physiognomy of the place, to what any ordinary hill top,—even the top of a very petty hill, of rounded outline and sober unimposing aspect, as well as quiet Neptunian formation,—might present. Yet not more than ten paces towards the north, there commenced the edge of a tremendous precipice, in its several ledges more than 1500 feet deep, running along all that side of the mountain, and forming in fact part of the internal wall of the great crater. The sudden discovery of this characteristic feature of a volcano, and in such close proximity to our tent, was calculated to make one tread the ground with more reverence.

After, several nights of unusual cloud, the evening of August 15th displayed a clear blue vault of sky, and the full moon starting from behind the purple summits of Grand Canary, commenced to establish almost a second day. The cloud referred to as unusual, was of course composed of the S.W. cirrocumuli, floating high in the air; for the lower N.E. cumuloni were never disturbed, from month's end to month's end, from their sluggish position below.

That there is a preponderance of clear weather on the night of full moon, and that such clearness is due to a dissolving of vaporous clouds, by heat reflected from the lunar orb, are ideas started by Sir John Herschel. While if he and other experimenters, have been unable with their most sensitive instruments, to detect any symptom of that heat, the want of success, he has suggested, may be due to the caloric being expended in upper parts of the atmosphere, in this very dissolution of vapour. And owing to its original low temperature, such lunar heat would have great difficulty in passing through, even a transparent medium.

Some confirmation of these views was at once found on this occasion; for the upper clouds had vanished before our eyes, under the presence of a full moon; and if the lower ones had not also disappeared, that might be considered only as a consequence of the higher strata, having exhausted the full potential energy of heat thrown upon them.

No very long residence at Alta Vista was needed to assure us, that this was the place, the centre as it were of the lava streams, defended by them from the winds, North, West, and South; but with a clear zenith view, and enjoying the most pellucid of atmospheres, or rather so little of any sort of atmosphere,—without question, this was the place, whereon to erect our friend, Mr. Pattinson's large Equatorial. True, that experienced local men had declared the bringing up of such a telescope to be impossible; but as the interests of science demanded that it should be brought up, I determined to descend the mountain, and see how the affair was to be managed.

There was plenty of useful work meanwhile for our men to accomplish at the station; the barewalled spaces having to be roofed in, and converted into habitable rooms. Towards this end, a large quantity of patent felt, and bundles of young fir poles had been procured in Teneriffe; in addition to certain beams, plates of glass, shutters, and door-hinges which had accompanied us from Edinburgh. With these materials, the sailors and Mr. Carpenter set zealously to work, on the morning of the 25th of August, just as my wife and I were leaving the station, with three Spaniards and three horses; of whom, one carried a portable meteorological observatory.

On the 21st of August, we rose early, excited alike by the novelties of the neighbourhood, and by the occurrence of another term-day. Our interpreter and his men had done their work famously in the preceding week, having erected altogether something like sixty yards of wall, four feet thick and six feet high; and so arranged, as to form a telescope enclosure in the centre, with cells or small rooms round about. One of these, intended subsequently for optical experiments, was soon furnished with half a roof over its southern end; and there we established the meteorological instruments.

The barometer was at 20·5 inches; the thermometer at 6 a.m., was 49°; and at noon, its maximum, was 65°. The air was thus found very sensibly cooler here, than on Guajara; while the dryness was rather less, the depression of the dew point varying from 18° at night, to 41° in the middle of the day. The power of radiation, however, appeared to be increased, and the inclination therefore, in the temperature, to mount up to a maximum with noon, became its marked feature.

The earlier part of the solar course, or from the eastern horizon upwards, could be well commanded at Alta Vista; but at 3h. 45m. p.m., the sun was lost behind the western lava ridges of the Peak; while other descending streams, on the immediate N. and S. of our station, cut off the lower part of the sky in those directions also.

Some three days after the storm, when our reduced party was engaged in packing up the telescope,—unexpected voices broke the stillness of the mountain air. Above the edge of the slope leading down to Estancia de los Ingleses, suddenly rose a head, and then the shoulders, of a stalwart Spanish peasant. His whole figure manifested itself quickly as he advanced, walking rapidly towards us. Behind him, other heads and other figures similarly rose up from the lower ground, with knapsacks on their backs, and iron-spiked poles in their hands, following their leader. When he had approached within a few paces, he doffed his hat, and pronounced the name of our friend, Don Martin Rodriguez.

The Don had sent a letter, and as usual, his men were not empty-handed. We rejoiced once more in his rich goats'-milk; as luscious as cream, and capable of being preserved in this high locality to the eleventh day, by boiling with a little sugar and water, and pouring into glass bottles. Then they produced a basket of fine fresh eggs, a luxury unknown for months, and a new goats'-milk cheese. We felt ourselves fortified once again, for another storm.

The leader of this party was a fine open countenanced fellow, a genuine specimen of the worth and strength of the country peasant. Our communications were not very fluent, from his understanding no other than his mother tongue, and our not having picked up much Castilian; but he was voluble in his inquiries as to how things had gone with us during the wet weather.

Soon after 10 o'clock, a.m., we were again meandering in long broken line on our upward way, with the clouds below, and a brilliant sun shining above. It was splendid climbing; a mountain ascent made very easy, was this riding up the gentle slope. Here we were, already at a height considerably above the top of Table Mountain,—to compare one of the islands with the continent, of Africa,—whose vertical precipices begin at half its height. But on Teneriffe, for upwards of 6000 feet, are still no greater average angles than 12° to contend with; and in most places so much soft soil, that after a shower of rain, there would be little difficulty in turning furrows with the plough, over a considerable part of the surface.

At 10h. 50m. we had reached a height of 4700 feet, and the first specimen was met with, of an interesting leguminous plant, to which we were afterwards to be greatly obliged, the “codeso” of the natives; the “adenocarpus frankenoides” of botanists. With closely packed composite leaves of light and warm green, a yellow flower, woody stem, branches like a miniature cedar tree, and with the bark of ages hanging about it, this specimen of the “legumineuses frutescentes” of the French savants, bore a certain acting resemblance to the “doorn booms,” or thorny acacias of South Africa, whose place it appeared to supply.

The method of “term,” or stated days, whereon meteorologists should observe throughout all the twenty-four hours, was an improvement introduced by Sir John Herschel, when studying the climate of South Africa. So admirably is it adapted to bring to light phenomena of short period, that I was happy when the morning of July 21st arriving, enabled me, with a semblance at least of utility, to begin the hourly observations of that particular term-day. At six o'clock, accordingly, the first entry of the series was made.

Our meteorological observatory was now pretty satisfactory as to arrangement, and was practically efficient in guarding against local disturbances. These were mainly two; first, the terrific radiation of the sun by day, with something of the same sort, but with an opposite sign, from the sky by night; and, secondly, the wind, which, if allowed its own sweet will, might at any moment blow all our instruments into the crater. To protect from these, a portion of a room had been erected, with walls to the S.E. and W., and with a bit of roof formed of planks and canvas, covered in with brushwood and weighted with rock. This roof was to keep out the almighty prying of a vertical mountain sun, whose rays did indeed try the nature of everything they had access to. The walls were of stone, and pretty nearly four feet thick, so that there was no fear of direct solar radiation getting through them.

Once within the parallels of the Trade-wind, every other natural phenomenon is found to give way before that grand commotion of the atmosphere. Therein does nature constantly seek—according to Lieutenant Maury's happy generalization—to restore to the air that moisture which was forcibly abstracted by the cold of the Polar circle; in order to be enabled, on passing into the opposite hemisphere, to distribute genial showers. The region of these winds appears eminently one of mechanical energy; for, driven by all the tropical power of the sun, its “cumuloni” clouds are ever hurrying along overhead, while the swell of the ocean hastens after them below; growing as it goes, and curling into foam, agitating and suffering agitation in a continually increasing ratio.

So we found it on board Mr. Stephenson's good yacht Titania, as she winged her speedy way to Teneriffe, with her important freight of astronomical instruments, in the latter end of June and beginning of July, 1856.

Her beautifully-formed iron hull bounded over the waves as lightly as a pleasure skiff, and with far greater velocity. But how she did roll! in manner not disagreeably,—for a delicate digestion was not disturbed,—yet that the quantity was most notable, let twenty measured angles, of 15° to 20° each, per minute, sufficiently testify.

September 26th saw us riding from Orotava to Santa Cruz.

During the first part of the journey, while still in that depressed or fallen-in region of the valley of Taoro; gardens were thick and close. Of their contents, none were perhaps so admirable as the double oleander; think of a rose-bush at least twenty feet high, and in a perfect explosion of flowers. Peaches were fine, as trees, but the fruit, strangely small; though numerous as the leaves. Date-palms, Phœnix Dactylifera, were not unfrequent; and after ascending the hill surface beyond the valley, villages were passed with almost groves of them. Yet none could be called well-grown. Stunted and stumpy they rather were, more like tree-ferns than palms; and whenever fruit appeared, it seemed dropping off immaturely. Whether the soil or climate be at fault, others must say. The latitude could not be, for in Egypt and Syria, several degrees north of Canary, date-palms wave on stems as tall and graceful as any in the world.

These countries, however, have no Trade-winds blowing on them every day, as in Teneriffe; not only bringing cold air from the Poles, but producing such mists through the greater part of summer, that the chief portion of solar heat, due to latitude, is reflected back to the blue sky, from a brilliant upper surface of an almost permanent sea of clouds.

Under such discouragement, vegetation along the northern coast of the island, is simply not so fine as it might be; with certain exceptions, there is more of the desert, than of the “scenery of plants.”

After our visit to the caldera of the Peak, with its walls of rock bleached by steam, and by acid vapours permeating them for ages, we could better understand the remarkable internal whiteness of lunar volcanoes, as shown by our telescope at Alta Vista.

Some geologists have, indeed, denied that the features seen by astronomers in the moon are to be considered as volcanoes; but we who duly noted the gentle external slope of some of those circular pits, their cliffy internal descents, their flat floors, and their central peaks—had little doubt in our minds. Occasionally could be traced something much like a collection of stony lava streams; which even the Spanish attendants, when looking by permission into the telescope, would call a Malpays. Generally too would they describe what they saw, with the same terms that they employed, for volcanic features of the mountain whereon we stood.

Could we have found in the moon, that dynamic trace, which was so important in proving relative ages among the red and yellow lavas of Teneriffe, viz., glacier wrinkles in one, and surf-like waves in the other,—all sceptical doubts must vanish. But we failed, and this point is left to a larger telescope, more constantly employed in lunar physics, on this or some higher mountain.

Details of a larger sort, however, were multitudinously brought out by the Pattinson Equatorial; to such an extent, indeed, as to be hopelessly beyond my poor efforts, to record them usefully in the small portion of time, that was available each evening.

The N.E. storm of the 1st of August, though exhausted of its greatest force in a few hours, was still dragging its slow length along through the following day. Every now and then a stray puff of wind came hurrying up, like a conspirator too late for the concerted rising, and throwing itself wildly against the northern cliffs of Gruajara, came spinning over their summits in the form of a little whirlwind. Sometimes, even our stone walls were enough to produce the effect; and then we saw an ordinary gust of wind blowing over the dry ground outside, raising a cloud of sand before it, and at the instant that it struck our wall, it eddied round the corner in a fine little revolving pillar of dust, occasionally entering our tent door in a most inconvenient manner. Amongst numerous young hurricanes which were thus generated before our eyes, one of them was remarkable for a regular increase in its diameter, as it travelled on, in a curving line; and for its diminishing velocity at the same time in the whirl. Mr. Redfield's theory, and Col. Reid's plates, of the West Indian storms, could not have been better illustrated.

Occasionally something more powerful came by; and one day, a heavy piece of canvas, ten feet square, spread out on the rock, was suddenly lifted up, whirled round and round in a horizontal plane, and then deposited again, as flat as before, almost in its former position.

The sailors expressed themselves delighted to see us again, and we were as pleased to witness the results of their active handiwork. There were now five rooms roofed in, round about the telescope enclosure; while along its inner southern side, ran a verandah, intended for meteorological instruments; and since discovered by the carpenter, to be a luxuriously calm place to sit in, when there was wind everywhere else.

This was previous to our return; for subsequently, the western gale grew so violent and squally, that there was no rest or defence for any of us. We were told, that a change had come over the weather during our absence, cold and dark, as if autumn had arrived. We looked to the thermometer and found it, on the morning after our return, 18° lower than when we had set off for the telescope; the air too was undoubtedly thick and turbid with dust-haze; but the chief change that had occurred, was in the appearance of the sea of cloud. Not only did this vast surface seem to have received a terrible shake, that had broken up its accustomed forms of long rolls of cumuloni, into short cumuli, but—an enemy had appeared in the field.

If there had been generally any part of the sea not amenable to influences of north-eastern wind, and not covered in by those clouds, it was to leeward of the Peak; there, long extents of water surface had been occasionally seen from Guajara.