Many fatal accidents have resulted from experiments made by people ignorant of the science. On the 6th of August, 1753, at Petersburg, Professor Richmann lost his life by endeavouring to draw the electric fluid into his house. Electricity, like many others of the arcana of nature, still retains almost as deeply shaded from human view as when its existence was first made known. Nature appears to have certain secret operations, which are not yet, perhaps, to be revealed. ELECTRIC TELEGRAPH. This is the most surprising invention of modern times, and of the greatest importance to a commercial people; by means of it intelligence is conveyed from one end of the kingdom to another, in the twinkling of an eye. A company was fully organised for the carrying out this invention, which commenced its operations in 1848, and established a system of no ordinary complication and extent. Their wires stretch from Glasgow on the north, to Dorchester, on the south, from the east coast, at Yarmouth, to the west, at Liverpool. These have brought upwards of one hundred and fifty towns into instant communication with each other. The wires set up for the use of the public alone are upwards of nine thousand eight hundred miles in length, and extend over a distance of two thousand and sixty miles, and, exclusive of those running underground, and through tunnels or rivers, are stretched on no fewer than sixty-one thousand eight hundred posts, varying from sixteen to thirty feet in height, and of an average square of eight inches, with an expensive apparatus of insulators and winders attached to each. As the most trifling derangement of the wires or apparatus will stop the communication, it is obvious that the utmost care and watchfulness is requisite to prevent and detect accidents. Accordingly, the whole distance is divided into districts, each district having a superintendent, and under him several inspectors, and a staff of workmen, batterymen, and mechanics, more or less numerous, according to the extent over which he presides.--When we consider these things, in conjunction with the central staff of engineers, secretaries, &c., at the head-establishment in London, a maximum charge of one penny per mile cannot be considered an exorbitant demand for the accommodation afforded to the public in keeping open so many receiving stations, and the maintenance of the expensive establishments. The telegraphic system is designed for important and urgent messages, and it may be safely averred that not one despatch in a hundred has been as yet forwarded by it, which has not been by many times worth more than the sum paid by the sender. A commercial house in Liverpool will scarcely grudge 8s. 6d. for a communication by which a necessary payment may be made, an important order given, or a profitable operation facilitated in London; and the message from Glasgow, which traverses a distance of five hundred and twenty miles in an instant, to summon a son from