Let, however, the difference between these powers be what it may, it is not greater than what exists among themselves in their respective classes, and which do not confessedly prevent their being upheld by the same substance. What can be more unlike than perception and volition, or more dissimilar than the vital powers and the mere mechanical powers of matter, viz. the forces of attraction, and repulsion? Is not the diversity in both these cases as great, to say the least, as between the spiritual and the vital powers? Yet none contend that the passiveness which distinguishes the faculties of perception and sensation, and the activity which marks that of volition, are, on account of their dissimilarity, characteristic of the attributes of different substances. No one contends that those vital powers, which, as if from design, assort, combine, and arrange, in opposition to, or in modification of, chemical and mechanical forces, and after an order and manner so consecutive and collocative, that the results apparently are as much indicative of an attention to final causes, as if they emanated from intelligence and volition no one, I say, imagines that these mysterious endowments inhere in a substance different from, though in union with, that which supports the mere mechanical forces, which, obeying a blind necessity, act irrespective of end or purpose. The incongruity, however, has not passed unobserved, and the truth is, that the restlessness of man's imagination would not have allowed him to remain content with two substances, if by any possibility of devising a third, he could have relieved himself of the difficulty of consistently apportioning among them so many dif ferent powers. But, unfortunately, it has been found, that even to produce the poor variety of material and immaterial substance, is not an easy task. In the grossness and straitness of our conceptions, we fix on solidity and extension as best suited to characterise the substance of matter. Confined to what passes within the mind, for a knowledge of things without, we take the effect and make of it the cause; we take the affections of a sentient being, and constitute thereof an insentient agent. In quest of something by which we may pourtray to our conceptions this substance of matter, and limited in our range to the impressions which it produces, we throw

back upon the causes their own effects, and are reduced to the necessity of tak ing the mental objects of our consciousness, wherewith to embody this otherwise unimaginable entity in a form for contemplation. But another substance being required to support the intellectual powers, we, in the extremity and indigence of our resources, are obliged to be satisfied with a negation, with the notion of a something, of which the utmost we can say is, that it is not solid: and extended that it is immaterial. The illusive importance of a name, however, it possesses in its designation of"spirit." The orientalists, not satisfied with a name and a negation, and passing by solidity, selected one of the more subtle sensations wherein to embody a conception of spirit and fire was its etherial essence. But this opinion is obsolete. There are those, however, in: the present day who are satisfied with a name without a negation, or any thing else, and accordingly we have a trio of entities-matter, soul, and spirit. How the third is to be discriminated, except by its name, it would be difficult to say. Do not these unprofitable and unfounded speculations expose the utter helplessness of our ignorance? They exh bit our blind and impotent, gropings after we know not what, and teach us, that snbe stance or essence is placed beyond our comprehension.

We see, on the one

hand, the ill-success and hopelessness of our efforts to obtain, though with the help of a negation, any allowable idea of more than two distinct substances; and, on the other hand, the insufficiency of these two to support the many powers, so importantly different, which nature exhibits. The conclusion from the preceding considerations generally, is, that we should not attempt to adjust and re-se coucile substances and powers, that an argument for a difference between the former cannot rest on differences observed between the latter, and that our dis tinctions of orders and kinds should not reach unto essences, but be confined to their attributes, with which only we are conversant.

preceding considerations; for this would be quite contrary to the spirit of the previous reasoning, which goes to show, that nothing is determinable herein but our own ignorance; that admitting the truth of the doctrine in question, we are not in possession of the slightest clue whereby to runravel the mystery; and that to assume to decide the question in any way, would ill-comport with that humble tone of inquiry, and that limitation of our researches, which the inductive philosophy recognises. Neither let it be understood that these views countenance in the slightest degree the doctrines of the materialists, for, as I have before intimated, they, by assuming along with their opponents a knowledge of the nature of matter, furnish the very ground on which rest the arguments for their own discomfiture. But, on the other hand, it is strenuously contended, and for precisely the same reason as before the limited extent of our discerning faculties—that the contrary proposition cannot be supported; that on this, the more orthodox side dogmatism is equally to be deprecated, and that it would betoken true wisdom and a becoming humility, if all parties would abandon the high categorical pretensions, in which, seduced by the prisle of reason, they are equally prone to indulge, and nintually and ingenuously confess that knowledge of this kind is too mighty for the mind of man. Intellectuals arrogance is fostered, whilst the understanding is benighted, in the pursuits of these dark and hidden themes; but orthodoxy, on the one hand, and heterodoxy on the other, take occasion of these suitable because indeterminable points, to raise the insigria of party, and to erect their equally presumptuous, unphilosophical, and unimportant systems. Better

would it be, and it is to this end the preceding considerations point, to acknowledge, with the doctrine in question, that maiter is known to us only in its powers, and to classify the different orders of being by the appreciable distinctions recognised among their powers, rather than by differences, which are as little to be comprehended as the essences to which they relate. Let ouir distinctions be such as may be universally perceived and understood; let them refer to matters of observation and experience; let ns have the wisdom to be wise enough, and debateable ground will not more belong to ntology than to natural history. Let

An Italian gentleman, Signor Leonardo Andervolt, of Spilinbergo, in the Friuli, informs us that he has invented an aerial locomotive balloon, capable of propulsion and direction at pleasure, with safety and precision, either with or against the wind. He has constructed, he says, a working model of this machine, with which he has actually traversed the air in his own country. He offers, if a certam sum of money be guaranteed to him in the event of his succeeding (of which– be entertains no doubts,) to fly over to England in his balloon!-Or that he will at his own expense construct a balloon here, which shall be able to keep up a regular traffic between any two points at a reasonable distance from each other, with even greater rapidity than any steam-boat or coach! The Signor does not ask a farthing until he has performed the foregoing conditions; but as his mechanism is so simple, that as soon as constructed it would be copied, and he might thereby lose the fruits of his ingenuity, he requires that a certain sum should be guaranteed him before doing so, either by a company or individuals, to whom he would assign his invention, secured by patent. Siguor Andervolti has left his address at our office.

The Signor speaks very fair; and as he asks nothing until he fulfils the conditions above stated, there could be no risk incurred were a number of individuals to subscribe for a hundred pounds or so. each, to secure so grand an invention. Of the thing itself we do not profess to give an opinion, we know no more of it than what is stated above.

Introduction.-It will be observed I have used the common method of counting the intervals of the diatonic scale, viz. by using Roman figures; and the chromatic scale is marked with small common figures, counting the interval from the first note named (but not included) to the next note required.

Of Keys.-The rule when not in use, i. e. the slide even with the ends of the stock (see fig. 1,) represents the only natural keys, viz. the upper part of the stock and slide show C not to require any sharps, because I. on the slide is opposite C on the stock; II. is opposite D; III. opposite E; IV. opposite F; V. opposite G; VI. opposite A; VII. opposite B ; and VIII. opposite C.

At the same time, I. on the (lower part of the) slide is opposite A on the lower part of the stock; II. opposite B; III. opposite C, and so on to VIII. opposite A; likewise A to be the relative minor key to C major. To find how many sharps or flats are required, and on which notes in any proposed key, you have only to set I. on the slide to the proposed key

note.

See fig. 2, where E major key is proposed, you will find I. on the slide under E; II. under F sharp; III. under G sharp; IV. under A; V. under B; VI. under C sharp; VII. under D sharp; and VIII. under E, the octave. Showing E major key requires four sharps; viz. F sharp, G sharp, C sharp, and D sharp; likewise the chords to the key note are seen at sight; suppose then opposite III. is G sharp, and opposite V. is B ;-if, then opposite IV. is A, and opposite VI. is C sharp.

Without removing the slide, it is seen that D flat is the relative minor, and requires five flats, viz. D flat, E flat, G flat, A flat, and Bflat, when ascending; be. cause, when a minor ascends to the octave, the semi-tone shown between the V. and VI. is removed to between the VII. and VIII; but in descending the semitones fall in their natural places.

Intervals, either diatonic or chromatic, are read off similar to the chords described above. In fig. 1, from C to A is a VI., or nine semi-tones.

Inversion is easily explained, as, for instance, see fig. 1: suppose a flat be found under E in the base-query, the thorough bass and its chords? It will be

seen under III. on the slide is a flat, which being under E on the stock, shows C to be the thorough bass note, E the III., and G. the V., &c. &c.

The chords of the seventh and its inventions are as easily applied.

Thorough bass and fundamental bass are explained by a similar process.

Chords by supposition, as the ninth, eleventh, and thirteenth are as easily managed, since the general use of the rule are to show the chords at sight, by having a figured base, or having a bass and an accompaniment to find the proper figures.

On the stock of the rule under the slide are figures (not shown in the drawings), showing the proper accompaniment to each individual note in the octave, either major or minor, ascending or descending.

An example or two by way of application:

In fig. 1, all this is explained without altering the slide.

The curve lines from I. to III., and III. to V., denote that the chord is from the tonic. On my rule I have three different coloured curves-the first denotes, as in fig. 1, the chord of the tonic; the second (not on the drawing) denotes the chord is from the subdominant; the third, the chord from the dominant.

W. ANDREWS. Near Ivinghoe, Bucks, Oct. 1, 1836.

MR. HOWARD AND MR. SYMINGTON.

Sir, I observe that Mr. Symington has not stated as I requested, "without reserve, where and in what manner my method of condensation had been in practice forty years. Why has he omitted to answer the latter part of the question? He taxes me with being out of humour, and with using towards him an authoritative tone. Suppose it to be so (which I do not however admit), does he not give me cause for it?

To bring the correspondence in your Journal on this subject nearer to an end, allow me to direct the attention of your readers, and more particularly of Mr. Symington himself, to the following extract from his original communication in your 677th Number, for I have not yet had leisure to inspect his specification :

By cooling down the water in the hot well to the temperature of the external water, by means of a pipe so placed outside the vessel, as to receive the direct action of the water, in order that condensation might be effected by injecting again and again a portion of the same water." Mr. Symington further refers in that communication to the superiority of this plan of condensation by injection, as a new method over that by external cold applied to the steam itself.

Now

this is precisely, and, I aver, beyond all cavil, the same process of condensation as that previously invented and carried into effect by myself, and of which Mr. Symington ought, at least, not to have been ignorant.

There is this difference only in the detail, that he proposes to lead the cooling pipe outside the ship; whereas, I lead it through the cold water within the ship. He may deem this an improvement in the arrangement-I beg to differ with him; but an improvement in the effect, I know by practice it can hardly be, for my plan accomplishes all that can be desired. However, he is welcome to it, apart from the appropriation of my invention, if in itself it be found new or advantageous.

Does not Mr. Symington perceive that his repeated reference to the drawings accompanying our specifications is admitting the weakness of his cause? My drawing is that of an arrangement by which the invention is rendered practically efficient; and the pumps there shown, by which the refrigerating pipe is supplied and the injection effected,

present an advantage over the (I admit rather more simple,) plan of making use of the air-pump and hot cistern, as usual, in so far as the power required to work this air-pump (say 1lb. per square inch on the steam piston,) is nearly all saved. But it happens that the process under this more simple form has been practised, and is at work in the Vesta steam-packet, now running daily to or from London, and Southend, and Sheerness.

Perhaps

in the next vessel, or may be on land, I may think proper again to alter the detail. But the principle or method remaining the same, and having shown in my specification, and since publicly carried into effect, a perfectly éfficient arrangement, which I thought the best at the time of enrolment (and I still think it so on the whole), I appeal to you, Mr. Editor, from your knowledge of patent business, if under such circumstances (putting it merely as a general question,)

am not entitled to vary the details, and, at the same time, to prevent others from appropriating the invention itself by doing so; and further, if this be not the true reading of the patent law, whether, in your opinion, any patent whatever for a new invention can be worth one farthing ?*

I may just add (Mr. Symington having alluded to the subject in his communication before referred to), that by means of a simple contrivance (in the Vesta) I have obviated the liability to accident arising from the condenser or the airpump, in the common mode of withdrawing the injection water by it, becoming choked with water under the unequal motion of the engines in a heavy