the density and elasticity of the steam already formed, so that the increase of temperature given to the steam, is not only attended with an increase of pressure, but also with an increase of density: experimental tables have been constructed, giving the relation of the elasticity, temperature, and density of this steam. The steam that is thus raised, in contact with its water, is said to be in a state of saturation with respect to watery vapour, and then the steam has the greatest density it can attain under the given temperature; but if this steam be separated from the water, and additional heat applied, the relations of temperature and density of saturated steam no longer exist, for whilst the temperature of the steam is increased, its density is no longer increased by fresh supplies of watery vapour.

Black and Watt concluded from their experiments, that the sum of the sensible and latent heat of a given weight of saturated steam is always a constant quantity, or in other words, that steam at any given pressure contains the same quantity of caloric that there is contained in the same weight of steam at any other pressure. Thus, if L be put for the units of latent caloric in a pound of steam at T temperature, then, according to this law,

L+T=1146-6; or L=1146.6

This simple law, until very recently, was universally adopted by natural philosophers; but the experiments of Regnault have shown, that the total units of caloric in a pound of steam increase with the sensible temperature of the steam.

If λ be put for the total units of caloric in a pound of steam at T temperature, then the law discovered by Regnault will be expressed by the formula

λ=1082 +305 T.

This law shows, that in order to raise the temperature of saturated steam one degree, there must be 305 of a unit of caloric added to that steam. The fraction 305 may be regarded as the specific heat requisite for maintaining steam in a state of saturation: it is the caloric required to raise the temperature of saturated steam one degree.

Example.-Required the latent heat of saturated steam at a tempera

ture of 300°.

Here T 300; hence we have, by Regnault's law,

A, or the total caloric = 1082 + 305 x 300 = 1173.5. .. the latent caloric = total caloric sensible caloric.

= = 1173·5 — 300 =873.5. Now, according to Black and Watt's law, we have

L, or the latent caloric = 1146.6 300 = 846·6,

giving an error of 26:9 in this case.

-

It will be observed, that a large proportion of the heat employed in our steam-engines is taken up by the steam in the form of latent heat, and this latent heat performs only a small proportion of the work done by the engine this constitutes the great defect of our present form of the steam-engine. Mr. Joule, of Manchester, has shown that a unit of caloric, acting under the most favourable conditions, is capable of performing about 770 units of work; now our best steam-engines do not perform more than one-third of this work. Hence we are led to conclude, that we have not yet attained the most economical mode of applying steam power.

F

DISCIPLINA REDIVIVA-No. 9.

SOME REMARKS UPON MORAL PHILOSOPHY.

HIS branch of mental science* calls for special consideration.

It

great field

of probability in which we live and move." It is peculiarly the science of human life and human necessity. As such, its study is calculated to discipline the largest region of human intelligence, and that under the light and steady influence of the largest human responsibility. As men, our minds are less naturally directed to the contemplation of what are called scientific truths, than to the observation and analysis of those phenomena of human conduct which accompany us and bespeak our presence in the natural world. As men, we cannot fail to receive the impressions of the true philosopher of morals. He finds the principles of his philosophy in the hearts of all, and can speak to us in a language which is at once scientific and familiar. When engaged in the study of moral philosophy, we exert the power of self-consciousness in a manner quite distinct from religious self-contemplation. This attitude of the mind, generalizing upon the symptoms and the facts of its own being, is the philosophical attitude.

The province of moral philosophy is not under the exclusive jurisdiction of any one class of inquirers. It is common ground, so to speak, where all have right of pasturage, and to which all may find ready access from the field of their own restricted inquiries. It is the philosophy of natural and revealed religion alike. It has two aspects or characters: the one theoretical, wherein it is regarded as a science, dealing with principles alone-the science of morals; the other practical, in which it may, in some sense, be considered to be an art,—the ethical art, or the laws of moral science reduced to a system of rules and practical prescriptions.

"Moral philosophy," says an able writer, "must not be confounded with ethics, properly so called, or with casuistry; its province is of a higher order, its subject-matter more comprehensive; it is not merely to furnish admonitions and exhortations to duty, nor to solve difficult questions of rare occurrence; if it be entitled to the name of philosophy, and to take its place among the sciences, it must search after principles; it must ascend to the source of duty and obligation; it must examine the nature of man, and analyze his mental faculties; and must lay the foundations of morals in the phenomena of mind. In a word, its busi

* Cf. the scheme of the mental sciences given at p. 362 of Mr. Thomson's "Outline of the Laws of Thought."

Reason

Mental Sciences

Choice and

Logic; or, the science of the forms of thought. Metaphysic; which examines the ground of all knowledge of things.

Morality; founded on the conception of right. Affection Esthetic; founded on the conception of beauty.

"The proper study of mankind is man."-Pope. The very fact that this line of the poet is a hackneyed" quotation, is surely, in itself, significant.

Cf. "Outline of the Laws of Thought," as quoted in last paper, for the difference between laws and rules, p. 439.

ness is to teach men their obligations, and the reasons and principles of them. As these obligations branch out into the duties of citizens no less than individuals, it comprehends political science along with ethics, properly so called; as they have their origin and root in the feelings and affections of our intellectual nature, it is closely and inseparably connected with mental philosophy. Moral philosophy, then, in its widest sense, comprehends all those subjects which are most interesting and important to the welfare of individuals and communities."*

The task of the moral philosopher is connected with most weighty and comprehensive considerations. The field of his scientific labours has been again and again invaded by the enemies of revealed religion, and he will find in it, therefore, abundant work of the very highest character marked out for him. As a believer in revelation, it is his business to examine the analogies of nature, and to exhibit them in their harmonious significance as witnesses to the great scheme of man's redemption. Religion is more frequently assailed under cover of a specious affectation of morality, than openly and on the ground of its positive teaching. Arguments insidiously based upon the rule of expediency (countenanced, as that rule has been, in the ill-considered theories of certain moralists), are, in effect, more injurious to the fabric of divine truth than the whole array of direct offensive hostility sustained by acknowledged adversaries. It is from considerations of this kind that we are disposed to attribute peculiar importance to the study of moral philosophy, on the part of a certain section, at least, of the community.

It is an acknowledged fact amongst Oxford men, that the highest part of their training—that to which they are most deeply indebted—is the discipline derived from the methodic study of moral science, as pursued through the period of their residence at the university. If there were no other ground for gratitude to Alma Mater there is this, that they were duly inoculated with a philosophical habit, through the careful, and as some might say, the dangerously exclusive study of Aristotle's system of ethics. Again and again we have heard this willing tribute paid by men in all stages of their career, subsequent upon leaving Oxford. And, by the way, we may observe, that it is no slight honour to the other great university to have confessed the claims of a sister in the province of her own peculiar study, and to have listened patiently to one of the most distinguished and faithful of her sons, interpreting the language of the greatest moral philosopher that modern times have seen. We allude to the impulse given to the study of moral science by one from whom we hope to be permitted shortly to quote.

We would now briefly urge upon a portion of our readers some considerations connected with the study before us. Some of those whom we hope to address, are not unlikely, at some future time at least, to be called to a position of responsibility in connection with the great questions of human life, and human action, and human obligation. To those who look forward to taking any part in offices of judgment, whether as adjudicators or the assessors of justice, we would point out some features in the relation of ethical studies to law and its administration.

The tendency of a complicated system of jurisprudence, based as it is

* Mills's Essays and Lectures, pp. 157, 158. Oxford: W. Graham. 1846.

in many of its positions, upon principles of expediency,* is not, throughout, directly advantageous to the growth of a sound philosophy in the minds of those who have to direct or influence its operations. It may indeed be hurtful to them, if they are not in the habit of recollecting themselves in the midst of manifold technicalities, and reverting alike to the first principles of right and to the condition of humanity in relation to the operation of those principles. On the other hand, how beneficial may we not conceive it to be to the young lawyer to seek in moral science at once a relaxation from the restraints of artificial obligations, and an unbending of that constrained attitude of mind which the study of human law, as such, necessitates. In moral philosophy he rises, so to speak, into that higher atmosphere, in which considerations other than human are allowed to mingle with and temper justice. He has, at such times, an ear for the complaints and for the bitter remonstrances of human frailty (ay, and of a more subtle equity), of which he must, in his inn of court, be heedless. He has an eye for other circumstances, in the cases submitted to him, than those which can be comprehended in the severe formularies of judicial defence and impeachment.

By such studies, and by an induction from the facts and phenomena of human action that meet him in his official course, he might aim at acquiring a philosophical depth and comprehensiveness of grasp, which would season invaluably that unprofessional opinion which it is permitted even our judges, along with their sternest decisions, and much more on occasions of public social interest, to pronounce. Here, we contend, is a field of most interesting study opened up, on the confines of a severe professional province, and that field is embraced within the limits of the science of which we are speaking.

Religion needs such students and such teachers as these, beyond the limits of her own sacred offices,-men sitting on the seats of judgment, and pronouncing not upon the merits of theological questions (into which faith and its accessories peculiarly enter), but upon those many problems of human action, and of a larger educational discipline, in which the cause of justice is so deeply interested, and upon which its most exalted secular advocates are signally authorized to pronounce.†

But to proceed with our subject. "Difficulties may press around us at every step in the investigation of such subjects as moral philosophy

*Certain principles of expediency do enter rightly into the scheme of national justice; but they enter into it in such a manner, and in such subordination to the higher ends of justice, as not to discredit the solid foundations of law, as laid deep in the principle of right, and witnessed and approved by "the general voice of mankind."

66

+Such signal advocates religion and truth do find amongst the judges of the land. The example afforded by such men as the late Serjeant Talfourd, and by many other lights still burning in the golden candlesticks of justice, is a possession (kτnua es aɛ) to all who would, after their measure and by a consistent devotion, exalt that righteousness" which in its turn "exalteth a nation." In peace and in war, in courts of law and in the quiet assemblies that spring of a growing desire for enlightenment (we know that we are using a dangerous word), there is much room for many workers; men of that quiet wisdom and character which is the growth of discipline; men of that large faith, which can commit the issue of its labours to other means than those under its own sole control, and which is not what the world calls liberality; men who have a definite belief and a definite religious purpose, which binds them, but teaches them anon that patience, which should be, in a world like this, the smoothest-worn side of many-sided charity.

presents; we may be continually baffled in our expectation, but the truth, though partially, will not be entirely concealed; and the imperfect knowledge we gain will amply reward the labour employed; and, like the alchemists in their search after gold, even if we fail of success, we shall meet with many valuable discoveries by the way, to be employed for the benefit of ourselves and others. Inquiries of this kind, if properly conducted, impart strength, acuteness, and elevation to the understanding, beyond any other studies whatever; and the man who has been trained at an early period of life in this course of mental cultivation, will be sensible of its advantageous effects in every branch of investigation, whether practical or speculative, to which he may subsequently devote himself. The graces of poetry and eloquence may be necessary to adorn the temple of knowledge, but its foundation and its pillars must be erected on that capacity for solid thought which moral and political sciences are best calculated to create and mature. And considered in this view, without reference to any direct consequences, they have been well compared to the crops which are raised, not for the sake of the harvest, but to be ploughed in as dressing to the land.' ”* Thus much has been said with the view of inducing to the study of moral philosophy. We have spoken of it as a science with whose general scope and functions our readers are supposed to be familiar; but before concluding what, amid much occupation at the busiest period of the year, must be a short paper, we propose to consider one or two points which would be useful to any one taking up the study without much opportunity of direction, and which may serve as a nucleus to his inquiries. We shall take occasion also to suggest the characteristic value of certain books on the subject, both ancient and modern.

To quote the Introduction to Dr. Whewell's "Lectures on the History of Moral Philosophy in England," +" Schemes of morality, that is, modes of deducing the rules of human action, are of two kinds :-those which assert it to be the law of human action to aim at some external object (external, that is, to the mind which aims), as, for example, those which, in ancient or modern times, have asserted pleasure, or utility, or the greatest happiness of the greatest number, to be the true end of human action; and those which would regulate human action by an internal principle or relation, as conscience, or a moral faculty, or duty, or rectitude, or the superiority of reason to desire. These two kinds of schemes may be described respectively as dependent and independent morality. Now, it is here held, that independent morality is the true scheme. We maintain with Plato, that reason has a natural and rightful authority over desire and affection; with Butler, that there is a difference of kind in our principles of action; with the general voice of mankind, that we must do what is right, at whatever cost of pain and loss. We deny the doctrine of the ancient Epicureans, that pleasure is the supreme good; of Hobbes, that moral rules are only the work of men's mutual fear; of Paley, that what is expedient is right, and that there is no difference among pleasures, except their intensity and duration; and of Bentham, that the rules of human actions are to be obtained by casting up the pleasures which actions produce."

* Mills's Essays and Lectures, pp. 159, 160. Oxford: W. Graham. 1846. Introductory Lecture, pp. ix. x. London: John W. Parker.

1852.