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All things in Heaven and Earth gathered together in Christ. Universal Respect to the Truths and Precepts of the Gospel inculcated.

God the Author of the Christian's Vocation and Attainments. Jesus Christ exalted, to give Repentance and Remission of Sin.--Humiliation, Prayer, and Reformation, recommended --Renewed Men intimately connected with Jesus Christ. God the chosen Portion of his peculiar People. The Presence of God the Felicity and Joy of his Servants. The Sources of Joy in God our Saviour.- Jesus Christ glorified God, and finished the work assigned him.-The amiable Condescension of Jesus Christ.— The Happiness of being under the Care of the good Shepherd.--The Conversation that becometh the Gospel of Christ.--Fi. delity to Jesus Christ urged by Assurance of glorious Recompence.'

Where every paragraph is alike respectable for evangelical truth, good sense and useful tendency, comparatively but little room is left for selection. We shall therefore take a specimen at hazard. The following is from a discourse intitled God the chosen Portion of his peculiar People.

If your hearts are indeed supremely fixed on God as your chief and satisfying portion, if you are entirely devoted to his service, and yield to him the homage and subjection he justly claims, and of which he is so infinitely worthy, you diligently improve the ordinances that God hath appointed. An eminent practical writer observes, " that men worship they know not how, because they worship they know not whom.” The sacred ordinances of divine worship are instituted by the Lord God, as part of the homage which he requires, as privileges that ought to be highly valued, as talents, for the use of which we are responsible, and as means of spiritual improvement and growth in grace. Do you then attend on divine institutions as your bounden duty, which you must not neglect? Do you consider them as a high privilege, for which you are amenable to the great lord of all ? Do you view them as talents with which you are intrusted, that you ought to occupy until he come to call you to account? Do

you
look

upon them as means of holding intercourse with God, and of attaining the most precious benefits ?

Viewing them as rich donations granted to the church by the exalted Saviour, do you wait upon God in them, in humble dependance on his mediation for

acceptance, solicitous to enjoy the gracious presence of God, and the transforming efficacy of the Holy Spirit? Hath the Most High rendered them effectual to turn you from darkness to light, to convince you of sin, to enlighten your minds, to awaken your consciences, to ele. vate your affections, to confort your hearts, and direct your ways? Con. sidering them as the appointments of the all-wise God, admirably adapted to promote the most excellent purposes, are you earnestly desirous to be favoured with his blessing and presence in them, and do you approach hini with engaged hearts, that you may see his goings, feel his power, behold his glory, and receive new testimonies of his loving kindness?' Vol. II. pp. 180. 181. We would just observe, in conclusion, that as these

are neither too long nor too abstruse, they are vot ill adapted to be read in families.

sermons

Art. V. Philosophical Transactions, of the Royal Society of London.

For the year 1810. Part 1st. 4to. pp. 147. Nicol, Pall Mall. THE 'HE first part of the Transactions of the Society for the

present year contains sis papers, of which we shall give, according to our usual plan, as brief an abstract as the nature and importance of the communications will permit..

1. The Croonian Lecture. By William Hyde Wollaston, M. D. Scc. R. S. Read Nov. 16, 1809.

This communication is not one of those elaborate compositions, wbieh have usually been produced under the title of the Croopian Lecture, but consists of some observations on three subjects not very intimately connected with each other.

The first division is on the duration of muscular action. That interval of relaxation, alternate with the contractile efforts, of which all continued muscular action consists, is obvious to the most superficial observations; but Dr. W. is of opinion that each effort, though apparently single, consists in reality of a great number of contractions, repeated at intervals too short to be visible, unless they are prolonged beyond their usual duration, either by a state of general or partial debility. The proof offered by Dr. W. of the existence of these very minute alternate notions, is the sensation which is perceived on inserting the extremity of the finger into the ear, which he compares to the noise of carriages at a great distance passing rapidly over a pavement.

• The rapidity of the motion varies according to the degree of force with which the finger is retained in its place. The sound then perceived is not at all dependent on the degree of pressure upon the tympanum; for, on the contrary, the vibratory sound is most distinct when that pressure is slight, if the finger be at the same time ren. dered rigid by the forcible action of antagonist muscles; and when the ear is stopped with great force, without the presence of mus. cular action, no such sound is produced. For instance, if the head be rested upon the hand, in such a position, as to press with its whole weight upon the ball of the thumb applied to the ear, no noise is perceived, unless the extremity of the thumb be at the same time pressed against the head, or unless the action of some other muscles be communicated to the ear, by any inadvertence in the method of conducting the experiment.' p. 3.

The number of the contractions was ascertained by the simple contrivance of resting the elbow upon an horizontal board, in which a number of equal, and equi-distant notches were cut, while the ear rested upon the bole of the thumb, and then comparing the number of those passed over in a given time by a pencil, or any other rounded body: the via

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brations appeared to coincide with the tremors, produced by the pressure of the thumb.

The average estimate was from 20 to 30 in a second; the highest number observed was about 35 or 36, and the lowest 14 or 15.

On Sea Sickness. Dr. W. refers this very singular sensation to the effect of mechanical pressure upon the brain, occasioned by a disturbed state of the circulation of the blood. During a short voyage he observed, that he almost imperceptibly acquired the power of resisting sea sickuess by accommodating his respiration to the uneasy motion of the vessel. The effect of this almost instinctive accommodation, Dr. W. conceives to be chiefly, if not entirely, upon the motion of the blood; since by a full inspiration during an uneasy pitch of the ressel, the chest is dilated, the blood allowed to circulate more freely through the pulmonary, organs, and the temporary pressure of the blood upon the brain in a measure counteracted or relieved. That such pressure does actually take place during sea sickness, Dr: W. infers from the principal uneasiness being felt during the subsidence of the vessel, by the sinking of the ware on which it rests; for it is during this subsidence that the blood has a tendency to press with unusual force upon the brain. In the natural erect position of the body, Dr. W. observes, the brain sustaios no pressure from the mere weight of the blood; and the vessels of the lower parts of the body must contract with sufficient force to resist the pressure of the whole column of bloud from the head downwards. If, howerer, the

support on which the body rests is removed, the blood no longer rests on its vessels, but they both fall together by the action of gravitation ; and the contraction of the vessels, which before supported the weight of the blood, will now occasion it to press upon the brain, with a force proportioned to its former altitude. This effect will of course take place, in some degree, during the gradual subsidence of a vessel from the falling of the wave on which it rests, and the partial reaction which is thus occasioned upon the brain is relieved by a full inspiration. The effeci of the motion of a ship upon

the
mercury

in a baronieter is analogous to that described above, and the sickness occasioned by swinging, Dr. W. thinks, is to be attributed to the same cause, as the uneasiness is perceived only while the body is descending forwards.

The contents of the stomach and intestines, Dr. W. supposes, may probably be affected in the same manner as those of the blood vessels; and he ihinks his theory receives conformation from the giddiness or fainting occasioned by with

drawing blood too quickly from the head, which sometimes happens when a person, previously fatigued, rises suddenly from an inclined position ; perhaps, too, the almost instantaneous cessation of sea sickness on stepping on shore is enti:ely a mechanical one.

On the Salutary Effects of Riding and other Modes of Gestion. In estimating the advantages to be derived from exercise, an important distinction has been overlooked between active exertion and passive gestation; and fatiguing efforts bave thus been often substituted for motions which are both agreeable and invigorating, when adapted to the strength of the invalid, and the nature of his indisposition. Dr. W. refers the beneficial effects of external motion, to the valves distri. buted through the venous system; which, while they allow the blood to be pressed forward by any thing which assists its progress, oppose an immediate obstacle to any thing having a contrary tendency. The heart is thus assisted in The great work of restoring a system which has recently struggled with sonie violent attack; or it is allowed, as it were, to rest from a labour to which it is unequal, when the powers of life are nearly exhausted by any lingering disorder.' The beneficial effects of gestation, in the opinion of Dr. W., are not to be limited to cases of absolute deficiency of power to carry on the usual circulation, but are equally applicable to those in which comparative inability arises from a redundancy of fluid to be propelled; and he relares the case of a gentleman, in whom a violent and visible throbbing of the heart, bad occasioned suspicion of organic mischief, who was effectually relieved by driving in a carriage over several miles of pavement, while in search of medical advice.

II. The Bakerian Lecture. On some new Electrochemical Researches on tarjous Objects, particularly the Metallic Bodies from the Alkalues and Earths, and on some combinations of Hydrogene. By Humphry Davy, Esq. Sec. R. S. F. Ř. S. E. MR. I. A. Read November 16, 1809.

The interest of the Bakerian Lecture, does not diminish in the hands of Mr. Davy, and in the present instance it is rich in valuable and important matter.

The first division of it consists of

Some New Experiments on the Metals from the fixed Alkalies These experiments are intended, chiefly, to elucidate the theoretical view, held by Mr. D., on the subject of the new discoveries. It is well known to our scientific readers, that be considers the metals obtained from the Alkalies as simple bodies; but other chemists, have offered and supported different yiews of the subject.

The first of the hypotheses here examined is that of M. M. Gay Lussac and Thenard, who suppose potassium and sodium to be compounds of their respective alkalies and hydrogene. This opinion they have deduced from some experiments, (detailed in the Mem. d'Arcueil) in which the whole of the ammonia, absorbed by the potassium employed, was reproduced ; part of it in its original form, and the remainder as nitrogene and hydrogene. The whole of the ammonia being reproduced, they contend, that the hy; drogene cooled during the absorption of the ammonia, must have been supplied by the metal. It must be observed, that only of the ammonia was reproduced by heat alone; the addition of water being necessary to the evolution of the remaining š; and that pure Ammonia according to the experiments of Berthollet, Jun. does not contain any water.

The experiments related by Mr. D. appear to us, however, fully to confirm the explanation which he drew from those detailed in the appendix to the last Bakerian Lecture. They were made in a tube bored out of a piece of solid platina; and the results of two are stated, in which the most scrupulous regard was given to every circumstance which could influence them, and in which the coincidence was nearly perfect. Three grains and a half of potassium absorbed 7.5 cubic inches of ammonia, and 3.2 of hydro. gene was evolved. The compound, covered with dry mercury, and gradually heated in the plantina tube filled with hydrogen, until it was intensely ignited, gave 9 cubical inches of gas, of which only of an inch was ammonia; the remaining 8,8 inches consisting of 5.8 hydrogene and 3 nitrogene; so that 7. 8 of ammonia, which by electrical decomposition would have afforded 3.4 nitrogene and 9.7 hydrogene, when decomposed by potassium, gave 3.16 ni. trogene and 8.54 hydrogene. The loss of hydrogene is consequently proportionally rather greater than of nitrogene, though the reverse has been the case when tubes of copper or iron were employed. Many similar experiments were - made; and in all of them a considerable quantity of black matter separated, while the potassium in the tube was acted upon by water. It was a fine powder having the lustre of plumbago, and was a conductor of electricity : it burnt at a temperature below ignition, leaving nothing but minutely divided platina : when heated in oxygene, the gas was diminished, and some moisture condensed which proved to be mere water. Mr. D. says he has advanced no further in ascertaining its nature, than to determine that it is platina combined with a minute quantity of matter, which affords

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