these inquiries are directed is, to furnish to the mariner practical rules, by which he may be enabled so to manage his ship when overtaken by a gale, and so to steer his course, as to avoid the fury and danger of the storm. Several highly useful and practical rules of this kind, derived from the investigations of Mr. Redfield, are already established, and may be found in his published papers on this subject, and in Colonel Reid's work.

Although Professor Olmsted regards Mr. Redfield and Colonel Reid as having satisfactorily explained the laws which govern these great storms, yet he thinks we are here, as in the case of the smaller tornadoes which occur on land, very much in the dark with respect to the ultimate causes of these phenomena―the causes which first produce the whirlwind, and afterwards maintain its violence. Heat, more than any other known cause, disturbs the atmospheric equilibrium, and produces winds; but the lecturer regards all attempts hitherto made, to explain the manner in which heat acts to produce the peculiar effects exhibited in tornadoes and hurricanes, as unsuccessful.

LECTURE VI.

Of Thunder Storms.

To Dr. Franklin is universally conceded the honor of having first established the identity between electricity and lightning. This he did by actually drawing the lightning from the clouds by means of a kite, and proving that it possessed all the properties of the electric fluid, even to the charging of a jar.

This discovery led to very extravagant notions respecting the agency of electricity in the phenomena of nature. Not only thunder storms, but storms of every sort, and all other meteorological phenomena, as dew, fog, rain, hail, and luminous meteors, were at once ascribed to the same universal agent. Indeed, the arcana of nature were now held to be all unlocked, and to electricity were successively ascribed the tides, the motions of the heavenly bodies, and the functions of animal and vegetable life. This propensity to employ electricity as the agent by which to explain all mysterious things in nature, not otherwise accounted for, has infected natural philosophy even to our own times, and many now imagine they have sufficiently explained any unusual or wonderful occurrence in the natural world, by calling it "an electrical phenomena."

In thunder storms, we are presented with the following leading facts. It is found by experiments, (made by raising kites to the region of the clouds,) that all insulated clouds are highly charged with electricitythat the electricity of a cloud is sometimes positive, and sometimes negative that even a fog is often highly electrified. Electricity is strongest when hot weather succeeds a series of rainy days, or when wet weather succeeds a series of dry and hot days. Thunder storms usually occur in the hottest seasons of the year, and after mid-day. They are more frequent and violent in hot than in cold countries, and are especially violent in volcanoes.

In our explanation of the foregoing facts, we must consider, that here are two different classes of phenomena to be accounted for: first,

the common elements of a storm of rain; secondly, the thunder and lightning. Now, the winds, the clouds, and the rain, are to be accounted for here in the same manner as in other cases. Opposite winds of different temperatures, hot and cold, and largely charged with watery vapor, meet, and moisture is precipitated in the form of clouds and rain, in accordance with the general principle before assigned for their production. But whence is the electricity? Whenever water is rapidly turned to vapor, or vapor is condensed into water, electricity is rapidly evolved. Such is its origin in thunder storms. It is therefore a consequence, not the cause, of thunder storms.

Our thunder storms usually take place as follows:— -After a hot morning, with the wind from the southwest, (the hottest quarter,) a northwesterly or westerly wind sets in, which is very cool. A thunder storm is the consequence, according to the principles above explained. Our morning thunder storms are produced in a different way, namely, by an easterly wind of very different temperature from that over the land, (being warmer in winter and colder in summer.) If the wind from the sea is hot, the elements of the storm will be precipitated from it by the influence of the colder air over the land; if the sea air is cold, it will precipitate the same elements from the hot and humid air then prevailing over the land. Hence a morning thunder storm, being caused by an easterly wind, is the precursor of foul weather; while an afternoon thunder storm, being caused by a northwesterly wind, is the precursor of fair weather.

On applying the preceding explanation of the cause of thunder storms, to the leading facts before mentioned, we may understand something of the nature of the various appearances. The clouds of a thunder storm being good conductors of electricity, and surrounded with air, which is a non-conductor, are analogous to the prime conductor of an electrical machine, only instead of a few feet of surface, as in the prime conductor, we have here a conductor of many thousand acres. The rapid evaporation which occurs on a hot summer day, and the sudden condensation of vapor in forming thunder clouds, evolve great quantities of electricity, which is accumulated in the clouds. As some clouds are found to be positively, and some negatively electrified, we easily account for the electrical discharges, which are nothing more than the passage of the fluid from one cloud to another, differently electrified. Every thing is here on a grand scale; for, instead of the spark of a few inches, which is all we can effect with our best machines, the flash produced by the apparatus of the skies, is sometimes three miles in length. Instead of discharging itself to a distant cloud, the electricity sometimes darts to the east, and then it tears asunder whatever comes in its way, and destroys the lives of men and animals. The flash of light accompanying an electric discharge, is no part of electricity itself, but is elicited from the air, which is suddenly and powerfully condensed before the fluid, and light is thus emitted, as in a little instrument called the air-mallet, in which a solid piston suddenly forced down upon a column of confined air in a cylinder, produces a spark sufficient to light tinder.

We occasionally observe a succession of phenomena, as follows: first, a vivid flash of lightning; shortly afterwards, a loud clap of thunder; and after a longer interval, comes a sudden fall of rain. This looks as though the electricity produced the rain; but were these events to occur

in the order required by our theory, namely, first, the condensation of the vapor into drops of rain, and secondly, the evolution of electricity in consequence of such condensation, the phenomena would reach us in the order observed. For the light being instantaneous in its passage, would reach the eye the moment the electricity was discharged; the sound being a slower traveller, would next reach the ear; and, finally, the rain, which travels much more slowly, would reach us after a considerable interval.

The lecturer closed with some practical directions for the construction of lightning rods, and for securing our safety during thunder storms. Lightning rods should be made of one continued rod of iron, the parts being secured into each other, and not broken by joints or links like a chain; it should ascend above the ridge of the house to a height equal to half the space to be protected on every side; (thus, a height of ten feet will protect a space of twenty feet in all directions from the rod ;) it must terminate above in three branches, tipped with gold leaf, or points of platina or silver, and enter below into the ground to the depth, where the ground is permanently moist, usually not less than six feet.

Professor Olmsted remarked, that when lightning rods were constructed on these principles, he had never known any injury done by lightning, and he entertained the most entire confidence in their efficacy. He urged the importance of every householder's availing himself of this easy protection, especially where a house stands separate from other buildings, as in the country. The numerous pointed objects in a city, have a tendency to dissipate the fluid, and to render it less liable to do injury, than in more secluded situations. The cases where life is destroyed by lightning, being usually much scattered, and involving but one or two individuals at a time, they attract little public notice; yet the entire amount of lives lost in this way every year, is greater (as has been ascertained by an accurate account kept by Mr. Redfield) than that occasioned by steamboat accidents.

EMBARRASSMENTS. -A man who has any feeling of honor, would rather die outright than become a bankrupt, and any reasonable sacrifice he would willingly consent to. Misfortune is one thing-imprudence another—and knavery the climax. When a man is unfortunate, he is deservedly an object of sympathy. To such, I would say, the moment you find yourself in embarrassed circumstances, and perceive that you cannot extricate yourself, without speculating with what does not belong to you, call a private meeting of your creditors, and lay before them the entire state of your affairs. Make a proposition of what you think you will be able to pay, towards the liquidation of their claims, and trust to their generosity to accept it. You will then be taken by the hand by your creditors-get a release and perhaps, with their kind assistance and advice, become a better man of business than ever you were,—but keep nothing back.-Foster.

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ART. VI.-BANKS OF MASSACHUSETTS.

THE banks constitute a very important interest to the people of Massachusetts. There are about twenty thousand persons who are interested as stockholders, and there are several times as many others who are dependent upon these stockholders, and thus whose means of living are affected by the condition of these institutions. The whole mass of the people, in their capacity as bill-holders and in respect to their various employments, have an interest in the continuance and prudent management of the banks. In fact, it will be difficult to find an individual who is not directly nor indirectly interested in them. There is hardly any thing whose influence is so completely felt in all the ramified relations of society. We are scarcely aware of their importance till we experience a disturbance of the currency, of which they furnish by far the largest proportion. Every species of property depends for its value in some degree upon the banks. They in a great degree control the price of all kinds of property and of labor, regulate agriculture, trade, and manufactures, and, in a series of years, show their effects on the progress of civilization. The change which has taken place in the condition of the people of Massachusetts, in the last thirty or forty years, is plainly indicated by the bank issues, which have constituted the greater part of the circulating medium.

In the following article it is proposed to show the condition of the banks of Massachusetts for a series of years, in respect to the value of the stock as an investment; in respect to the amount of specie compared with the circulation, and with the sum of the circulation and deposits, which is justly regarded as an important criterion of safety to the public; in respect to the increase of the capital stock; and in respect to the amount of the capital stock, and of the bills in circulation compared with the population, the bills in circulation having served as an important part of the circulating medium in the operations of trade, and as important means of changing the condition of the community. In preparing the tables, use has been made of the bank returns as published by the secretary of state.

Table showing the Average of the last semi-annual dividends per cent. of the Banks of Massachusetts, for thirty-two years, from 1808 to 1839.

According to the foregoing table, the average of the last semi-annual dividends of all the banks, for five years, from 1808 to 1812, inclusive, was $3 723 per cent. on the capital stock; since the one half of one per cent. has been semi-annually paid under the name of a bank tax to the state, the 269 and for 27 average from 1813 to 1839, has been $2 962 years during these two periods, embracing 32 years, it has been $3 08245 Supposing the other semi-annual dividends to have been the same, (and it is reasonable to suppose they were not materially different,) average annual dividends on the capital would be $7 45 per cent. in

the

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