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invents gauge-pipes to indicate both the
consumption of water and the production
of steam, by which the chances of acci-
dents are lessened and further control ob-
tained over the giant which men had set
to work. Additional command was ac-
quired by the introduction of the safety-ress of Watt began.
valve to Savery's engine by Dr. Desagu-
liers, a clergyman and lecturer on science
in London; until this improvement was
introduced the engine-worker felt in con-
stant dread of sudden explosions. The
draining of deep mines was the great ob-
ject to which these steam-engines were
devoted; but they were unable to raise
water more than ninety feet, a second or
a third engine being used in the case of
greater depths. Thus, if it were required
to raise water from the depth of two hun-
dred and seventy feet, the first engine
raised the water to a reservoir ninety feet
from the bottom; from this reservoir the
second engine raised it ninety feet more;
making in all one hundred and eighty feet;
when the third engine began its operation
and raised the water to the surface. A vast
expenditure of force was therefore neces-
sary in these machines, and an immense
outlay of fuel became requisite, all of
which were serious drawbacks to the effi-
ciency of the engines.

Thus, much was yet required to bring the steam-engine to its present high point as a moving force. Some improvements were effected by Newcomen, an ironfounder of Dartmouth, who took out a patent, and introduced his engines into extensive use; but these details need not detain us from the great inventions of the far-famed James Watt, who may be called the creator of the modern steam-engine, so numerous were his inventions, and so beneficial their results. To give an outline of his life is not our present object, but rather to describe the steps by which he perfected the machine and reduced its once irregular and dangerous movements to a beautiful precision and security.

Watt's attention was first called to the defects of the existing engines by the examination of one made by Newcomen, and he soon perceived the rich harvest of fame and profit in store for the man who should develop the full powers of the steamengine. He saw the mode in which this might be effected, and beheld the path leading to the temple of glory; but his instruments were too feeble to carry out

his vast designs, and for a period many a bright idea was secluded in his thoughtful, scientific mind. At length, Boulton of Birmingham became the partner of Watt, placing a part of his foundry at the disposal of his friend, upon which the prog

The production of improved machinery was absolutely requisite to produce that smoothness of motion essential to the easy working of gigantic beams, rods, and pistons, which should combine the easiest motion with the utmost tightness in the cylinder, in order to confine the highly expanded steam. Mechanists could not be found to execute such delicate works: workmen were therefore to be trained ere Watt could exhibit his clear conceptions in operation. Many pages would scarcely suffice to describe fully the severe and simple logic, the subtile contrivances, and brilliant theorizing, by which he developed many of his improvements; we must content ourselves, therefore, with a statement of results only. Many of these consist of former discoveries worked up to greater precision: thus the steam under the piston was condensed before the time of Watt, but he detected much clumsiness in the method of effecting this, and much incompleteness in the work, as all the steam was not condensed, and the descent of the piston was therefore partly resisted by the remaining vapors. A great loss of power was the inevitable result of this The attempt to correct the defect led Watt into some most abstruse calculations, which he was compelled to pursue by theory alone, and reached, at last, by a beautiful guess, the truth sought. He also saw that the injection of water into the cylinder at all must cool the piston as it descended, whereas this should be kept as hot as the steam itself, which otherwise would be turned to water and its power lost. To remedy this, another series of thoughtful investigations, descending into the deep mysteries of latent and sensible heat, became necessary before the difficulty was overcome.

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One of the most beautiful conceptions of Watt is shown in the arrangement called the "parallel motion," the object of which was to secure the steady and upright working of the piston; for in such rapid movements the slightest twisting of the works would soon shatter the machine. The production of such a direct motion

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may appear a simple matter, but it required made a study, and various improvements all the mechanical skill of Watt's well- in boilers, pistons, valves, wheels, furtrained intellect to solve the delicate prob- naces, and smoke-tubes, have rewarded the lem. The reader must remember that a perseverance of the engineer; and every day rod, suspended perpendicularly to one fresh discoveries may be expected to arise. end of a moving beam, will not rise and fall in a straight line, but in a peculiar curve.

Since the opening of the Liverpool and Manchester railway, fresh facts have been accumulating for the guidance of our landsteamers, and from the time when Fulton cut the waters of the Hudson, divers experiments have been yearly advancing the capabilities of steam navigation.

This divergency of motion must shake and loosen the works, so as to destroy their air-tight character. The problem proposed was to find a point in the rod, which, notwithstanding its oscillatory movements, should always remain in the same straight line; could this be discovered, the whole of the action might be kept free from undue vibrations. Such a point was found, and Watt enabled to apply all those improvements which depended upon the movement just described.

Whether this power of modern times shall continue its progress, or be laid aside for some combination of mightier forces, we know not; but, while we revere the divines, moralists, and poets, who have formed our earliest thoughts, let us also honor those who have disclosed a means of uniting remotest nations in one bond of fellowship, and carrying civilization to distant lands. The discoveries in physical science must not be deemed mere caterers for our bodily pleasures, but men commissioned to aid in extending the noblest interests of mankind.

Another step now made gave additional security to the steam-engine, and illustrated the skill of Watt in overcoming difficulties. A valve, called the "throttle," regulated the supply of steam from the boiler; but the care required for its management was more than could be obtained from any save the most attentive workmen. Watt resolved, therefore, to make his engine its own regulator; and, after a train of hard thinking, invented the machine called "the governor." The principle was, to secure some means of making the increased velocity of the engine the means of checking the in-rush of the steam, and so reducing the undue rapidity of motion; while a too slow movement increased the supply of vapor and accelerated the action. Thus the most perfect regularity was secured by methods which excite the admiration of all who are able to appreciate the beauties of scientific mechanism.

OXFORD PUNS.

DR

R. BARTON, warden of Merton College, was the oddity of his time. Of the puns belonging to Dr. Barton, we believe that the following is little known. As he was a man of remarkable insensibility, people told him everything that happened. A gentleman, coming one day into his room, told him that Dr. Vowel was dead. "What!" said he, "Vowel dead? well, it is neither u nor i." Dr. Eveleigh, who, with his family, was some years ago at Weymouth, gave occasion to old Lee, the last punster of the old school, and the master of Baliol College, Oxford, for more than half a century, to make his dying pun. Dr. Eveleigh had recovered from some consumptive disorders by the use of egg-diet, and had soon after married. Wetheral, the master of University College, went to Dr. Lee, then sick in bed, resolved to discharge a pun which he had made. "Well, sir," said he, "Dr. Eveleigh has been egged on to matrimony." "Has he?" said Lee; "why, then, I hope the yoke will sit easy." In a few hours afterward Dr. Lee died. The yoke did sit easy on Dr. Eveleigh, for he had a most amiable, religious, and charitable wife. - Chambers's Ed. Jour.

These instances are sufficient to indicate the nature of the numerous improvements introduced by Watt, whose efforts excited the emulation of a host of followers, who have carried the powers of the steam-engine to a degree beyond the most sanguine expectations of Watt; so that, while he could only promise a force sufficient to raise five hundred thousand pounds, others have furnished engines capable of lifting one hundred and twenty-five million pounds; thus giving an increase of power in the proportion of two hundred and fifty To these subsequent steps Watt, however, pointed the way; and since his time every part of the engine has been

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remedies, as well as the most healthful of luxuries, is so fully established by the opinion of the highest authorities, founded on the universal practice and experience of ages, that it is unnecessary to go over the beaten ground. I shall therefore proceed to observe, that the manner of bathing, though a point of the first importance, seems by most people to be thought of no consequence at all; but let the effect of bathing be considered, and this indifference will appear in a strong light.

By the compression of the whole external surface of the body, which takes place on judicious immersion, the blood is carried on with acquired force to the heart, and returned by the reaction with proportional impulse. By this increased action and velocity, the capillaries are opened, the sluggish and tenacious humors loosened, obstructions are removed, the vessels are cleansed, and the whole system is invigorated; but all this depends on total and instant immersion; and to suppose that stepping into a bath, or wetting the body by parts, will produce these effects, is an absurdity that one would scarcely think any person of the commonest powers of comprehension could admit; yet the practice of many people seems to imply as much, though even the most accustomed bathers have experienced, that when, by bathing in shallow water, they have necessarily wetted the lower extremities first, their breath has been taken away; whereas by plunging wholly into water of the same temperature, no such inconvenience has arisen a sufficient proof of the danger of partial bathing.

As by judicious bathing the vessels are freed, and the pores opened, so, by a contrary mode, the very reverse of these advantages must be expected. Everything beyond a single plunge and immediate immersion is preventive of the incalculable benefit which judicious bathing never fails to produce. By continuing in the bath,

the body is robbed of its natural heat; reaction prevented; the vessels collapse; and transpiration by the natural channel of the pores is suspended; obstructions are confirmed, and paralysis is frequently induced. It is common to observe the fingers of" dabbling" bathers void of the vital stream; and though habit enables some persons of robust constitutions to remain a considerable time in the water,

vigor of the frame. Even the exercise of swimming, when long continued, has in numberless instances occasioned the loss of the use of limbs, and not unfrequently proved fatal.

Some persons think it a laudable feat to leap head-foremost from a height into the water; but this unnatural posture must be injurious, except to those whose heads and heels are equally provided with brains. An easy and nearly horizontal position is the best for the moment of immersion.

It is frequently objected, that cold bathing is dangerous in internal and local weaknesses; but a close and attentive observation, as well as personal experience, lead me to think this objection at least equivocal. May not these weaknesses be occasioned by obstructions which the bath will remove? and as to the humors being forced on the peccant part, they are too briskly driven to rest anywhere; and it is at least as probable that the part affected, partaking of the power of this simple and natural tonic, may join in the general expulsion. I have myself bathed under pleuritic affection, which immediately abated, and by repetition was entirely removed. Similar consequences ensued on bathing with a face much inflamed and swollen from a violent tooth-ache. The same effects were produced in a case of head-ache, which had continued for ten days, with excruciating torture, and was nearly subdued by the first immersion, and wholly in a very short time. In short, I have scarcely a doubt that when evil has resulted from bathing, it has been from the injudicious manner in which it has been used.

In regard to the best time for bathing, it is when the natural indication is the strongest, and this, generally speaking, will be after considerable exercise (but short of producing sensible perspiration or fatigue). The body is then in that adust state which renders bathing so highly luxurious; and a vigorous circulation will

insure the full effect of reaction. Nothing then can be more operative of ill, or at least of diminished good, than lingering on the margin of the flood till the stagnating fluids refuse to obey even the spur of immersion. Hunger is the first sensation in a healthy body on rising from the repose of the night; and as digestion takes place in the most perfect manner during sleep, and many hours have passed without supply, the stomach should then be recruited. This, therefore, is not the most proper time for bathing. I consider the best time, generally, to be between breakfast and dinner; but every one will be able to determine this point, who is capable of a small degree of reflection, and will give it as much consideration as he often bestows on matters of less importance. Perhaps, where there is great rigidity of fibre, the morning may not be objectionable, and the warm bath may be a good preparative.

I cannot too often repeat, that every subsequent dip lessens the effect of the first immersion; and that the bath should be used once, and once only, every day; and were it so used every day in the year, it would insure a life of health, barring the effects of intemperance, and all other ill habits; though even these enemies to health and life will labor against such an antagonist. I cannot here help smiling at the idea, that three or four dips, twice or thrice a week, are better than one every day. I really should be provoked to call this notion absolutely idiotic, had I not met with persons of good sense who had fallen into this egregious error; and I knew a lady who actually took ten dips on the last day of her stay at a wateringplace, and would have gloried in her economical exploit, had not the chattering of her teeth, instead of her tongue, prevented her recounting it to her friends for at least ten hours after.

sures a perfect privacy, it were to be wished the imagination would not conjure up a phantasmagoria of merely ideal observers.

A part of my subject now presents itself, upon which I can never sufficiently expatiate while anything remains unsaid which may tend to enforce its interest; I mean, the bathing of children. The little innocents are entirely at the mercy of those into whose hands they may happen to fall; and the brutal or senseless indifference to their feelings, their fears, their almost convulsive apprehensions, is sometimes productive of the most afflicting consequences, and too often prevents any beneficial effect from bathing.

I am now to tread on slippery ground; but I cannot conscientiously avoid it, though I know I shall risk the displeasure of the real, but mistaken, delicacy of some, and the affected delicacy of more, when I urge the ill effects of using dresses in bathing; but I must submit to sensible and reasoning females, that an encumbering dress not only injures the primary influence, but by clinging to the person, checks the glow which should be felt on coming out of the bath, and in weak constitutions often totally prevents it. As the usual inclosure inVOL. III, No. 2.-M

Children should never be dipped more than once; and that with the greatest care, that the immersion may be deep, but quickly done. The practice of dipping them three times, (folly's magic number,) and generally without allowing them sufficient time to recover their breath, is so preposterously absurd, so evidently injurious, that one would almost wonder it could ever obtain. The child is made to look with increased dread to the hour of bathing, through the pain it has experienced from the distress which the lungs have undergone; by which the chance of benefit is reduced to almost nothing. Let parents, then, and all who have the care of children, weigh well these suggestions, and rescue the little sufferers from the hands of ignorance and inattention; that they may partake of the benefit of this invaluable remedy, preservative as well as curative. When a child knows that it is only to be dipped once, it will soon be reconciled; for it will be put to no pain; on the contrary, the sensation will be highly agreeable.

The proper depth for bathing is about four feet and a half; a less depth were disadvantageous, and a greater would be too deep for general use. Persons attending bathing-machines should be very attentive to this circumstance, as it will greatly contribute to the satisfaction as well as benefit of the bathers, who are seldom aware of its importance.

Volumes of cases might be adduced, incontestably proving the efficiency of the bath, and showing the absurdity of those apprehensions which some people have entertained respecting its application in particular complaints. There is much

more danger of deranging the frame, and occasioning local injury, by medicines uncongenial with the natural economy, and powerful in their sensible or less perceptible ravages, than can possibly be experienced in any case from judicious bathing. In a word, when the bath is used with due consideration and judgment, its advantages are certain and universal.

DEFECTS OF MODERN PREACHING.

HERE are many shams and worships,

pulpit almost entirely ignores, and by ignoring serves to perpetuate. It attacks licentiousness and gross vice; but it says little about the worship of money, about the cant of respectability, about the undue honor paid to "Right Honorable," and other great names-about the mean tricks of trade and frauds of commerce, and the innumerable white lies which abound in all the departments of society. It shuns, too, in general, all allusions to the political and social movements of the age-although, surely, the pulpit should be an eminence commanding a view of both worlds, and intermeddling on fit occasion with every subject connected with the welfare and the advancement of mankind. The consequence is, that people stepping out of the every-day atmosphere of life into the church, find themselves in a strange and perplexing atmosphere; they are less elevated than startled and tantalized; they hear little that comes home to their business and bosoms; they seem to have passed by a single stride into the sepulchral gloom of the middle ages, and when they leave the sanctuary, it is like coming out of the world of dreams. Ah! the church does not now overlook and lord it over the Strand-the congregated throng of menthey go on their own way, and it stands apart, uttering unregarded thunders, and shooting out flashes which too often are powerless as painted lightning.

The truth is, that while the age has progressed the pulpit has stood still. The style of modern preaching is not materially changed from what it was two centuries ago. The same explanation of the same texts; the same ever-recurring platitudes and commonplaces; the same boltless thunders of threatening and warning; the same sheet-lightnings of copious and ineffectual declamation; the same tone of

priestly insolence and hauteur; the same fierce and rancorous partyism abound, as they did in the past. Nay, some there are who would deliberately stereotype the mode of preaching, and insist that we in this day must reproduce the exact style and manner of the Covenanters or the Puritans, and that every minister to be successful must become a second Baxter, or a Rutherford Redivivus. This is not possible, and it were not desirable if it were possible. As well regret the loss of the grimaces which their preachers made and the strange

sung. Even

self, were he returning to the church, would in all probability change his mode of address. "Righteousness, temperance, and judgment to come," would still be his themes; the result would be again that Felixes would tremble at his oratory, his way to the heart or conscience would still be a terribilis via; but there would be important diversities in his tone, his language, the line of his argument, and the course of his appeal. Paul was inspired as a writer; but there is no evidence that as a preacher he was perfect, or meant as a complete or final model for us. Chrysostom did not preach like Paul, but like Chrysostom, even as Paul had not preached like Jesus, but like Paul; Luther did not preach like any of the three, but like Luther; Knox copied not Calvin in his preaching, nor Melville Knox, nor Chalmers or Hall any of them all. The beauty, power, and glory of preaching have always lain, if not in absolute originality, yet in new adaptation of old truth to new circumstances. And, on the other hand, the weakness, contempt, and degradation of preaching have lain, and do lie still, in slavish conformity to models in the form of sermon, abounding with the heads, and particulars, and inferences, the "ohs" and "ahs" of old sermons, imitating, too, their tone of sanctity, and accompanied by the whining, voice and the starched spect which belonged to a by-gone day. How many the preachers who seem to imagine that man's religion, like his life, lies in his nostrils, or who deem that length of visage is a measure for piety and power, or who mistake a compound of clamour and cant for eloquence, or who confound the mere phraseology and technical theological language of our ancestors with their living fire and solemn earnestness? These are the men who disgust and weary the young intelligence

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