checked, and the force must be developed more slowly, giving the rock time to open; and this is effected by first twisting the cotton into threads and then weaving the threads into hollow ropes. These may be introduced into holes drilled in any direction for the purpose, or inserted into seams of the rock, where gunpowder could not be kept in place.

The manufacture of General Lenk's gun-cotton, unlike that of gunpowder, consists of a series of operations which aro entirely free from danger. The material is acted upon in a wet or moist state, in which it is impossible to cause it to explode unless fire be actually applied. In the last processthat of drying the cotton-there might be danger if precautions were not taken against it; but, where the same care is exercised as in drying powder, no danger is to be apprehended.

In Prussia, a drying chamber was blown up in 1862; but this is attributed to the want of proper drying arrangements,-to the use of a stove with iron smoke-pipe. However, work had been carried on there for eight years without an accident till this time.

In the course of General Lenk's experience, which extends over a space of twelve years, only a single case of explosion has taken place, and this resulted from an improper speed in running the spinning machinery. Compare this with the experience of the proprietor of any powder-mill in the country, and who can present a record as favorable as this, though he has had the experience of thousands of others before him by which to guide his operations and guard against accidents?

Gun-cotton has been stored in the magazine in Hirtenberg for fourteen years. It has been transported by every means of conveyance, in black wooden chests, exposed to the sun for months, without a single accident, and without deterioration in quality.

In the summer of 1862, an explosion took place of the Simmeringer Haide Magazine, which contained gun-cotton and gunpowder stored together. The opponents of gun-cotton urge that this was caused by the spontaneous ignition of the gun-cotton; but the commission of chemists appointed to investigate the facts contend that, "with equal show of probability, it might have been imputed to the spontaneous ignition of the gunpowder;" and "this view might be supported by the experience of numerous powder-explosions, where not an atom of guncotton was present, and yet the cause was never ascertained."

The cost of gun-cotton has been found in Austria not to differ appreciably from that of gunpowder for quantities producing the same effects.

A few words in reference to the special arms for using guncotton may not be deemed inappropriate in this connection.

The Austrian gun-cotton field-artillery consists of four

VOL. I.-23

pounder and eight-pounder bronze rifled guns; the latter forming the reserve artillery. A battery on the war-footing consists of eight pieces. The four-pounder gun is drawn by four horses, and the eight-pounder by six horses. The four-pounder gun is forty-three inches long in the bore, and has three deep grooves, which make one turn in seven and a half feet. The cross-section of the bore is a portion of a spiral; this particular form being given to it for the purpose of diminishing the windage of the shot. This gun weighs four hundred and sixty-five pounds, and throws a projectile of eight and a half pounds.

The eight-pounder gun is similar to the above in its general construction; it weighs nine hundred and fifty-five pounds, and throws a projectile of fifteen and a half pounds.

The cartridge is formed of spun thread wound around a conical stick. It is preserved in transportation in a woollen bag, which is taken off before the cartridge is inserted in the bore.

It is found necessary to use the sponge after each discharge, to free the bore from the gases, the vent being left open during the sponging.

Gun-cotton is used exclusively for loading shells, whether intended for gun-cotton or gunpowder batteries, it having been found so much superior to gunpowder for this purpose. A fourpounder elongated shell charged with gun-cotton will be broken into one hundred to one hundred and twenty pieces, most of which will weigh from one to two ounces each; charged with gunpowder, it will be broken into only twelve to twenty fragments.

The musket has a small hole bored in the axis of the breechpin, and the bore at the muzzle is enlarged for a quarter of an inch. The cartridge is formed by first wrapping a spun strand of gun-cotton on a small stick inserted in the base of the ball, and finished by covering the strand with a piece of woven guncotton, resembling hollow lamp-wick, and securing it at the ends.

It often happens, in the excitement of battle, that the soldier loads his musket with two or more loads before discharging it. It has been found, on examining the arms collected on the battle-field of Gettysburg, that a large proportion of them were loaded with more than one charge, in some cases with ten and more, and in one instance with as many as twenty-three cartridges. Muskets thus loaded with gun-cotton would be torn to pieces, if fired; and, in order to guard against the possibility of inserting a second charge before the first was fired, a simple and ingenious device has been adopted. On the point of the ball is attached a pasteboard wad, which fits in the counter-bore in the muzzle, and remains there until blown out by the discharge of the gun. The cartridge drops into its place by its own weight, and the end of the stick entering into the hole in the breech-pin holds the cartridge fast, so that it is not displaced in handling the arm, though turned muzzle downwards.

As no rammer is required, the musket may be loaded when the soldier is marching at a double-quick pace.

The English Government has recently made experiments with the new explosive material, General Lenk having visited England, by invitation, for the purpose of assisting at the trials. More recently, the French Government has taken up the subject, and is now engaged in an investigation into the merits of this new gun-cotton. General Lenk is, at the request of the Emperor Napoleon, in France, to be present at these experiments. The attention of our Government was drawn to the success attending the experiments with gun-cotton, in Austria, by Mr. T. Carrisius, our consul at Vienna; and the Secretary of War, alive to the importance of this subject, has directed experiments to be made to determine whether its merits are such as to warrant its introduction into our service, in whole or in part. These experiments will soon be commenced.

There are many considerations which make it important for us that the subject should receive a full, fair, and impartial investigation. We are now dependent upon India for our supply of saltpetre. By the introduction of gun-cotton, we shall be enabled to substitute for saltpetre the nitrate of soda, which is found in South America, much nearer home and more easily to be obtained, and from a supply of which we are not so liable to be cut off.

We have a long extended coast to defend against new and most formidable modes of attack. Our large sea-coast guns, on which we may justly pride ourselves, will require the assistance of the most destructive explosives for their shells, and the most powerful submarine batteries that we can devise, to protect our sea-board cities from the attacks of hostile iron-clads.

Gun-cotton will not, probably, supersede the use of gunpowder: it may prove a valuable coadjutant.

EARLY FRENCH FORTS AND FOOTPRINTS OF THE VALLEY OF THE UPPER MISSISSIPPI.

OFFICERS of the army, when stationed at Fort Snelling, so boldly situated on a promontory of saccharoid sandstone at the confluence of the Minnesota and Mississippi, or on duty at the more secluded posts Forts Ripley and Ridgley, in looking at the locality on Nicollet's map marked "Ruins of French Fort,' have, with the writer, no doubt often wished there were some works in the English language imparting information concerning the old French régime in that region. After a diligent search, we have gathered a few facts, which are woven into an essay.

One of the most picturesque scenes in North America is the approach to Lake Pepin. For miles the steamboat ascending the Mississippi glides through an extended vista, crowned in the distance by an amphitheatre of hills which define the basin of the lake.

In the summer, the islands of the river, luxuriant with vegetation, and the banks flanked by abrupt bluffs of limestone, with cedar-trees standing like sentinels wherever root-hold can be found, make an impression which the traveller cannot erase in a lifetime.

Occasionally these steep walls of stone recede, with their fanciful outline of castles and battlements, and prairies, sufficiently elevated to be secure from the inundations of spring, appear, which were enticing spots to the ancient voyageur after a long and wearisome day's paddle in his frail canoe.

Just below Lake Pepin, on the west shore, opposite the mouth of the Chippeway River, is one of these beautiful plateaus, which captivated Nicholas Perrot, a native of Canada, who had been familiar from childhood with the customs and dialects of Northwestern savages, and who had been commissioned by the Governor of Canada as commandant of the West.

Near the site of the present village of Wepashaw, with twenty other bold spirits, he landed in the year 1683, and erected a rude log fort, the first European structure in that vast region, -a generation before New Orleans, two thousand miles lower down on the same river, was founded.

This primitive establishment, within the limits of the new State of Minnesota, on some of the old maps is appropriately marked as Fort Perrot. During the winter of 1683-84, the party proceeded to visit the Sioux above the lake, but were met by a large delegation descending on the ice, who returned, and escorted the Frenchmen to their villages.

In 1685, it became necessary for Perrot to visit the Miamis

to engage them as allies against the English and Iroquois of New York. On his return from this mission he was informed by a friendly Indian that the Foxes, Kickapoos, Maskoutens, and other tribes had formed a plan to surround and surprise the fort and employ the munitions of war against their enemies the Sioux.

With all possible speed the commander came back; and on the very day of his arrival three spies had preceded him, and obtained admission under the pretext of selling beaver-skins; and they had now left, and reported that Perrot was absent and that the fort was only guarded by six Frenchmen. The next day, two additional spies came; but Perrot, in view of his danger, devised an ingenious stratagem. In front of the doors of the buildings, on the open square within the enclosure, he ordered all the guns to be loaded and stacked, and then the Frenchmen were made to change their dress after certain intervals, and stand near the guns; and thus he conveyed the impression that he had many more men than the spies had observed. After this display, the spies were permitted to depart, on condition that they would send from their camp a chief from each tribe represented. Six responded to the demand; and as they entered the gates their bows and arrows were taken away. Looking at the loaded guns, the chiefs asked Perrot "if he was afraid of his children."

He replied, "that he did not trouble himself about them, and that he was a man who knew how to kill.”

"It seems," they continued, "that you are displeased." "I am not," answered Perrot, "although I have good reason to be. The Good Spirit has warned me of your evil designs. You wish to steal my things, murder me, and then go to war against the Nadouaissioux. He told me to be on my guard, and that he would aid if you gave any insult."

Astonished at his knowledge of their perfidy, they confessed the whole plot, and sued for pardon. That night they slept within the fort; and the next morning their friends began to approach with the war-whoop. Perrot, with the fifteen men under his command, instantly seized the chiefs, and declared they would kill them if they did not make the Indians retire.

Accordingly, one of the chiefs climbed on to the top of the gate, and cried out, "Do not advance, young men, or you will be dead men. The Spirit has told Metaminens [the name by which they designated Perrot] our designs.'

The Indians rapidly fell back after this announcement, and the chiefs were allowed to leave the fort.

In the year 1687, Perrot, Du Luth, and Chevalier Tonti came to Niagara, with allies, and united with Denonville in making a raid upon the Senecas of the Genesee Valley,-which proved unsuccessful.