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and single, but it appeared to be about double the distance that
it really was from the eye, and, consequently, to be magnified
in proportion.
XV. A Method of drawing extremely fine Wires. By Wil-

liam Hyde Wollaston, M. D. Sec. R. S.
The contrivance recommended by Dr. Wollaston for this
purpose, is extremely simple, and of very easy application in
practice. A wire of gold or platina, is to be introduced into
the centre of a rod of tine silver, which is then drawn into fine
wire by the usual means. As silyer wire used for lace and em-
broidery, is frequently as fine as the sto of an inch in diameter,
if the gold wire introduced into the centre of the rod has is
the diameter of the silver, then, when it is drawn into wire of
sts of an inch, the diameter of the gold will be gooo of an
inch, and of such wire 550 feet will weigh only one grain. By
these means, however, Dr. W. reduced platina to the extreme
tenuity of Tour of an inch in diameter, but the tenacity seemed
to be impaired when the fineness exceeded mooo of an inch,

Toto and wire of this diameter supported of a grain before it broke. The silver coating is easily removed from these wires by nitric acid; but, as when they exceed in fineness the poor, or modo of

. an inch, they are managed with difficulty, from being easily disturbed by slight currents of air, and from being nearly invisible, and not at all perceptible to the touch ; Dr. W. recommends that the silver coating should not be removed from the extremities, and by this means they are kept stretched, and are easily applied to the purposes for which they are wanted. XVI. Description of a single lens Micrometer. By Wil

liam Hyde Wollaston, M. D. Sec. R. S. This instrument is admirably adapted for the purpose of measuring the diameter of the extremely fine wires, which are occasionally employed in the construction of philosophical instruments. Its external form is that of a common telescope, cunsisting of three tubes. The scale by which the object is measured, occupies the place of the object glass, and consists of a series of small wires about of an inch in diameter, equidistant from each other, and formed into divisions by a regular variation in the length of the wires with a view to facilitate the computations of the observer. This then forms a scale

equal parts. The lens is placed at the smaller end of the instrument, and having a focal length of only be of an inch, it admits a small perforation to be made in the brass mounting at the distance of about' t of an inch from its centre, through

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which the divisions of the scale can be seen distinctly by the naked eye, on account of the smallness of the aperture through which it is viewed. The object to be measured is placed between a pair of plain glasses which slide before the lens, and which admit of adjustment by means of a screw, and the lens also has a small motion by means of the cap, for the purposes of adjustment. As the indications of the scale must be different according to the distance to which the tube is drawn out, it is necessary to determine these with precision, before the instrument is completed. In Dr. W.'s, instruments each division of the scale corresponds to rotoo of an inch when it is at the distance of 16-6 inches from the lens, and since the apparent magnitude in small angles, varies in the simple inverse ratio of the distance, cach division of the scale will correspond to zobor of an inch at the distance of 8-15 inches, and the intermediate fractions totoo, moto, will be found at intervals of 1-66 inch. These intervals should be marked oa the outside of the tube.

In order to determine the value of each division of the scales with accuracy in the first instance, on which the excellence of the instrument must depend, it is necessary to employ a wire, of which the diameter has been determined with great care, for any error in this process, will, of course, pervade all the future admeasurements for which the instrument may be employed. Dr. W. recommends, for this purpose, that the diameter of this wire should be deduced from the specific gravity of the metal. The specific gravity of gold, for example, being 19-36, a cylindrical inch will weigh 3,837 grains, and consequently a wire of pure gold, drawn out fifty-two inches in length, shall weigh five grains, and will be of the diameter of to of an inch. The accuracy of the instrument will be still greater, if this method be pursued with several wires of different diameters, but weighed with equal care, and the subdivisions of the exterior scale made to correspond to the average of their indications.

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XVIII. On the Tusks of the Narwhale. By Sir Everard

Home, Bart. F. R. S. Much uncertainty has prevailed on this subject, and the general report of those persons who are employed in the Greenland fishery has been, that the female Narwhale is destitute of tusks, and that the male has one only. From one of these persons (Mr. Scoresby, jun.) Sir Everard Home received the skull of a female, in which the sutures were firmly united, and yet there was no appearance of tusks, though a male skull.

which appeared to be about the same age, had a tusk four feet long.

These facts then afforded some evidence of the truth of the general opinion of those employed in the Whale-fishery; but on reference to Anderson's description of Iceland, Greenland, and Davis's Straits, published in 1684, Sir E. found an account of a female skull which had been brought to Hamburgh, and which had two tusks, the left being seven feet five inches long, and the right, seven feet. And in another work, published in 1700, by Tycho L. Tychoricus, he found an account of a skull, having the left tusk seven feet long, and the right, imbedded and completely concealed in the skull, nine Danish inches in length. In consequence of these contradictory

. statements, the skulls of the Nar-whale, in the Hunterian Museum, were examined by means of the saw, when the rudiments of the tusks, not yet protrudled from the bony substance, were

liscovered. In two male skulls, in which the left tusk was seven feet ninc inches, and four feet respectively, the right tusk (about ten inches long) was completely imbedded in the bone, and was still more than seven inches distant from the front of the skull. In one of the specimens there was an external opening, leading down to the point of the tusk. Sir E. considers these as milk tusks; they are perfectly solid throughout, while the full grown ones are hollow nearly through their whole length. The left task, therefore, appears much earlier than the right; and so rare is it to meet with an instance in which they are both visible, that a captain of a Greenland ship, who had been thirtyfive voyages, informed the Author, that he had once only, and that from the mast head, seen a male Nar-whale with two tusks. The female skull, sent to Sir E. by Mr. Scoresby, when cut into, was found to contain two milk tusks, similar to those in the male : they were about eight inches long, and had advanced to within two inches and a quarter of the front of the skull, and here was a canal leading from the point of each to the external Furface; the tusks, therefore, appear much later in the female than in the male. These facts prove that the name Monodon Monoceros, given to this species by Linnæus, is an improper one.

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Art. IV. The Lives of the Puritans : containing a Biographical

. Account of those Divines who distinguished themselves in the Cause of Religious Liberty, from the Reformation under Queen Elizabeth, to the Act of Uniformity, in 1662. By Benjamin Brook, 3 vols. 8vo. pp. xxviii, 1515. Price 11. 16s. Black, London. 1815

(Concluded from our last Number.) WE avail ourselves of the present occasion to furnish our rea

ders with a concise view of the origin and progress of Religious Liberty in England ; referring them for particulars, to Mr. Birook's Introduction, which fills å hundred pages of the first volume. It is a good summary of ecclesiastical history, for the period which it comprises.

The passions of men sometimes afford the occasions of good, which their principles would never present; and the methods which they employ for the gratification of their sensual or anbitious appetites, are directed by the invisible hand of God, to ap end which never entered into their contemplation. This was remarkably the case with Henry the Eighth, whose opposition to the papal power, did not originate in the love of true religion. pot was it intended for the advancement of Freedom. Strongly attached to the Romish Church, and honoured by its head with the title of Defender of the Faith, as a reward of his service in advocating the cause of the Church against Luther, there was bo probability that the English Monarch would become an instrument of impairing the pontifical authority, and of delivering kingdoms from its grasp. His passion for Anne Boleyn, however, produced, eventually, in England, effects similar to thos which, in other countries, resulted from the religious intrepidity of the Reformers. Inflamed by passion, and irritated against the supreme Pontiff, who opposed obstacles to its gratification, by hesitating to divorce him from Catharine his queen, he resolved on the adoption of measures, by which his project of a umion with Anne Boleyn might be accomplished, and his resentment manifested against the Pope. He claimed the supremacy in his own kingdom, and compelled the clergy to sube: to his authority as the head of the Church ; and thus dissom the connexion wbich had long subsisted between the ecclesiastis of England, and the papal court.

This change of the supremacy was in favour of liberty. though the king maintained it in the most absolute manner. was an innovation on the established usage of ages; it broke the spell of superstition, and divested the authority of the Church of that veneration which gave it the air of sanctity. The chang of power, also, was in itself a circumstance which could not as of affording excitement to the reflections of men ; and as it r made at a time when the Continent was agitated by religious a

troversy; while the sparks struck by the energy of Wickliffe's doctrines were yet alive ; and when the art of printing was prepared to aid in the diffusion of knowledge; it was an event of great importance in the history of religious freedom. The grounds on which a temporal prince rested his title to spiritual dominion, were sure to be examined by some superior mind, which would pronounce this authority a usurpation, and contest its claims. This assumption of supremacy was resisted by the clergy; but the royal power bowed them to its will. The refusal to acknowledge this authority, was afterwards a cliaracter

a of the Puritans, as it is now of Dissenters; we perceive, however, that before the rise of the Puritans, the principle of resistance to religious dominion in princes, was avowed by the ministers of the Church.

The supremacy of a layman over all ecclesiastical persons and things, is a gross anomaly in a Church which boasts of its supposed apostolical constitution, and contends that bishops are exclusively the order of men to whom Christ has committed its government! Laymen preside in the ecclesiastical courts as the king's judges ; and their authority is not only independent on the bishops and clergy, but it inay give sentence in opposition to their interests and their will. In the Church of England, even excommunication is not an act of the clergy. The government of the apostolical Churches, was essentially different from the ecclesiastical policy of England. Of whatever excellence, therefore, the Established Chureh may boast, she is not entitled to affix the epithet Apostolical to lier designation.

Though Henry discarded the authority of the pontiff, he still retained most of the tenets of the Church of Rome; and while he persecuted and burnt Protestants for denying the real presence, he put Papists to death for refusing to acknowledge his supremacy. In 1539, the Bloody Statute of the Six Articles, was enacted, establishing transubstantiation, communion in one kind, the celibacy of the clergy, vows of chastity, private masses, and auricular confession, and it awarded death as the penalty of their violation. The reading of the Scriptures in the common tongue, which had been conceded, was now prohibited. This haughty monarch was thus trampling, with proud disdain, on the rights of faith and of conscience, when, in 1547, death delivered his subjects from his tyranny.

On the dernise of Henry the supremacy was exercised by the Council, into whose hands the Government was committed by the late king's will, during the minority of Edward the Sixth, his son and successor, then in his tenth year, and was used with comparative moderation ; yet, in some instances, it was exerted with rigour and cruelty, as in the severities towards Middleton, and in the execution of Joan Bocher, which has affixed an in

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