The many friends of Dr. Joseph Hooker (says the Editor of the Gardeners' Chronicle) will rejoice to know that the last Indian Mail, Oct. 6th, has brought intelligence of his perfect safety amidst the dangers of his adventurous journey. On the 5th of July he was encamped in a fine country in the Sikkim Himalaya, where the ground was carpeted with splendid plants. The rains were incessant, food scarce, and the Bhoteeas troublesome; the bridges between his camp and Darjeeling had been swept away by the floods, and communications could only be maintained by a most circuitous route. His collections will prove of the highest interest. Among other things, his Rhododendrons amounted to at least thirty species, many of which are much finer than those already published: no botanist had previously ventured to attempt the examination of the Rhododendron region east of Kamaon, - an operation surrounded with most serious difficulties, for these plants can only be studied during the rains. He had also found a magnificent Rose, with scarlet flowers larger than the palm of a man's hand; and crowds of other remarkable species.

* The soil which Mr. Turner uses for these flowers is the top spit of a meadow taken off long before it is wanted, and frequently turned, in order to clear it of wireworms: it is by no means heavy soil; the only addition it receives is about one barrowful of good decayed stable-manure to three of loam. Sufficient material for the following year is mixed every August, and, as we have stated, the loam is always in store some time before it is wanted. Rather a plentiful supply of weak liquid manure is given the plants during June, if the weather is hot, with a view to assist them in throwing up their blossom-shoots.

Dr. Hooker #1

A genuine love of flowers, and an ardent desire to enhance the value and beauty of our already rich collections of exotic plants, tempted, as most of our readers know, this distinguished traveller to visit the hitherto almost unexplored Himalayas with a view to send plants and seeds to Britain. The results of this great undertaking have been eminently successful. Amongst other things, he has discovered many magnificent new Rhododendrons, of which seeds and plants have been received at Kew. Objects of natural history, as well as several additions to our Orchidaceous plants, have also been received from him; and until lately he has been allowed to pursue his useful and pleasing avocations without much molestation; but our readers will be sorry to learn that he and Dr. Campbell, an officer in the East India Company's service, are now in the custody of a petty hill-chief called Rajah of Sikkim. This information is derived from a letter written by Dr. Hooker himself on the 12th November, and superscribed, "All well, 24th of November," and which he contrived to smuggle away by the fidelity of a servant, with a scanty hope that it would be allowed to reach its place of destination, as it did, by the Marseilles mail, which arrived on the 21st ult.

The Southampton mail, on the 26th, brought a part only of a letter of an earlier date (Lachoong Valley, Oct. 25th, 1849), or rather two continuous letters, but ending abruptly, giving an account of a visit to the plains of Thibet; from which the following brief extracts may prove of interest.

"We have spent four days in Thibet! It was, however, a serious undertaking, and required a combination of fortunate accidents, together with all my previous knowledge of the country. It was again by the Lachen Pass that we entered, and we met with a great friend in the Tcheba Jama, a man of intelligence and vigour. Scarcely had we reached the Thibetan frontier, than I set spurs to my pony, and galloped a-head, as far as possible, over the sandy plains, determined to see all I could. The elevation of 17,000 feet made any rapid movement so fatiguing, that my animal soon gave in; and I was obliged to pursue my way on foot up the Lachen, in an easterly direction, and at the back of Kinchin-jhow, over sandy or stony dunes, interspersed with a little grass, tufts of nettle, Carex, an Ephedra, and a thirsty-looking Lonicera, only a few inches high.

" Proceeding north-east from Kongra Lama, I had long stony rolling moun tains to the north and to the east; while to the south, the stupendous snowy mass of Kinchin-jhow rose almost perpendicularly from the sandy plains. As the country was so traversable, I judged it best to follow the Lachen to its source near the Donkiah Pass, which I wished to be, if possible, our return route.

" Late in the day I arrived at the Cholamo Lakes, within sight of the Donkiah Pass, but with my pony so knocked up, that I had the greatest difficulty to drag him after me. Here, however, I refreshed him with some tufts of green Carex, and led him gently back, suffering myself severely from headache, caused by the sun's intense heat; for at this elevation (nearly 18,000 feet) a slight amount of exertion brings on headache. The evening was considerably advanced before I met my friends. When we proceeded, a party of Chinese soldiers followed us, their Ding pun (or Lieutenant) mounted on a black yak (Bosgrunniens)! He was surrounded with pots and pans, bags, bamboo-bottles containing butter-milk; his tent, blankets, and other possessions, were all heaped on the same yak, and he, perched atop of all, looked like a gipsy on a laden donkey. The rider was;i small withered man, arrayed in a green coat; his Tartar cap surmounted with a brass button. Behind came the sepas (or soldiers), enormous ruffianly-looking fellows, dressed in blanketing. Each was armed with a pipe, a large knife, and a rude long matchlock lashed across his stern.

The matchlocks of the Chinese are always carried slung at right angles across the hip; they are very rude weapons, and have a pronged support or rest, which falls up with a hinge, and projects like an antelope's horn beyond the muzzle. These ungainly weapons worn behind and at the lower part of the back gave the sepas a most comical look. They came in marching order, took no notice of us, and camped close by. We pitched our tents within a low cattle-enclosure on the open plain, burning yak's dung for fuel. The cold was intense, and the wind violent and dusty; the sky brilliantly blue. We resolved to remain here for a day of two".

Immediately after this passage (says the Gardeners' Chronicle, from which the above information is mostly derived) the narrative breaks off abruptly; it is only from another, yet we believe authentic source, that we learn that it was on their return into Sikkim after another attempt, but an unsuccessful one, to enter Thibet at a more eastern pass, the Rajah thought proper to send a band of soldiers, who entered the tents while our travellers were totally unprepared: they were suddenly and at the same instant seized, each by a separate party; their arms bound behind them with cords (in Dr. Campbell's case, it is said, accompanied by cruelty); and they were conveyed to the residence of the Sikkim Rajah at Tumlong, confined as prisoners, and not allowed any communication with each other. The R,ajah himself sent a letter conveying the intelligence to the Governor-General, who, in the kindest manner, has written to Sir William Hooker, with the assurance that he has replied to the Rajah's letter, demanding the instant release of the prisoners as a preliminary step to any treaty with him; and his Excellency confidently expects that the next mail will convey the welcome news of the gentlemen being set at liberty.

Since the above was in type, we have learnt with great pleasure that our enterprising traveller is released.