Various

“ Test for Lenses.—I beg to submit to a Country Practitioner the following very simple test for the coincidence of the chemical and visual foci of an achromatic lens:
Take a common hand-bill or other sheet of printed paper, and having stretched it on a board, place it before the lens in an oblique position, so that the plane of the board may make an angle with a vertical plane of about thirty or forty degrees. Bring any line of type about the middle of the sheet into the true visual focus, and take a copy of the sheet by collodion or otherwise. ”

“ John Lawson, B.D., Rector of Swanscombe in Kent, published A Dissertation on the Geometrical Analysis of the Antients, with a Collection of Theorems and Problems without solutions for the Exercise of young Students. This work was printed anonymously at Canterbury, but the merits of the essay did not permit the author to remain long in obscurity; the real writer was immediately known to most of the geometers of the day, and the elegant character of many of the theorems and problems, led to a general desire that their solutions should be published in a separate work. ”

“ In the Revelation we also find—
"And the angel, which I saw stand upon the sea and the earth, lifted up his hand to heaven and sware by Him that liveth for ever and ever," &c.—Revelation, ch. x. v. 5, 6.
Your correspondent inquires how oaths were taken prior to their being taken on the Gospel.
Among the nations who overthrew the Roman empire, the most common mode of swearing was on the relics of the saints. In England, I think, the most common mode was to swear on the corporalia or eucharistic elements, whence we still have the common phrase "upon your corporal oath." ”

“ But we think many will regret that, while pointing out the Notes and Emendations from which he dissents, Mr. Singer should not have noticed those which he regards with favour; and that, in his anxiety to vindicate the purity of Shakspeare's text from the anonymous emendator, he should have embodied that vindication in language, which, though we are quite sure it is unintentional on his part, gives his book almost a personal character, instead of one purely critical. ”

“ Chaucer was forty years old, or upwards, in 1372, when he was sent as an envoy to treat with the duke, citizens, and merchants of Genoa; and if, as is probable, he had translated Troilus and Creseide out of the "Lombarde tonge" in his youth (according to the testimony of Lydgate) , it is not unreasonable to infer that his knowledge of Italian may have led to his being chosen to fill that office. ”

“ Foreign saltpetre was not in equal goodness with that of our own country, and the foreign gunpowder far worse conditioned and less forcible than that which is made in England.
"3. Divers foreign estates had of date prohibited the exportation of salt-peter and gunpowder out of their own dominions and countries, so that there could be but little hope or future expectation of any peter or powder to be brought into this kingdom, as in former times, which would enforce us to make use of our own materials." ”

“ PHOTOGRAPHIC CORRESPONDENCE.
Washing Collodion Pictures—Test for Lens.—As I was indebted to the kindness of Dr. Diamond, amongst other friends, for my original initiation into the mysteries of photography, it may appear somewhat presumptuous in me to differ from one who has had so much more experience in a point of practice. I allude to that of washing the collodion negative after developing, previously to fixing with the hyposulphite of soda; but, probably, the reasons I urge may have some weight. ”

“ Singer, who has given us the result of his examination of them in a volume entitled The Text of Shakspeare vindicated from the Interpolations and Corruptions advocated by John Payne Collier, Esq., in his Notes and Emendations. No one can put forth higher claims to speak with authority on any points connected with Shakspeare than Mr. Singer, who has devoted a life to the study of his writings; and none can rise from a perusal of his book without recognising in it evidence of Mr. Singer's fitness for editing the works of our great dramatist, and feeling anxious for his revised edition of them. ”

“ Chaucer would naturally quote Latin and French, as being familiar to his cotemporaries, and would abstain from introducing Italian, as a knowledge of that language must have been confined to a few individuals in his day; and he wrote for the many, and not for the minority. ”

“ Secretary Murray is very bad: a party is just now sent for him, intelligence being brought where he is. I don't think we have lost thirty men, and not above five officers killed, amongst which are Lord Robert Ker, Captain Grosset: the rest their names I have forgote. We are now in full possession of this place. Some say the Pretender was in the battle, and wounded; but others say he was not. Such of them as are left are gone to Fort Augustus. The duke, God be praised, is in good health, and all the generalls. ”

“ Over all has been a canopy, or rather tester, for the whole must have originally resembled an antique and massy bedstead, exhibiting the very incongruous appearance of a husband in bed with two wives at once. ”

“ I there learned that in the village of Thornthwaite it was Chapel Sunday, and on inquiry I was told that there were a few other villages in the neighbourhood where there was also a Chapel Sunday. Upon this day it is the custom of young people to come from neighbouring places to attend worship at the village church or chapel, and the afternoon partakes of a merry-making character at the village inn. There appeared, as far as I could see, no excesses attending the anniversary, all being respectable in their conduct. Can any of your Cambrian readers inform me the origin of this anniversary? ”

“ By an act of the Lord Protector and Parliament, made in 1656, it was enacted that no person or persons should dig within the houses or lands of any person or persons of the commonwealth for the finding of saltpetre, nor take the carriages of any person or persons for the carrying of their materials or vessels, without their leave first obtained or had. ”

“ Apropos of A. E. B.'s clever Note, permit me to say, that though at first it appeared to me conclusive, I now incline to think that Shakspeare intended Helen to address the leaden messengers by means of a very hyperbolic figure: "wound the still-piecing air that sings with piercing" is a consistent whole. If, as A. E. B. rightly says, to wound the air is an impossibility, it is equally impossible that the air should utter any sound expressive of sensibility. The fact of course is, that the cannon-balls cleave the air, and that by so cleaving it a shrill noise is produced. ”

“ To graft scions of delicate wooded trees on strong stocks, occasions an over-supply of sap to the grafts; and though at first they seem to flourish, yet they do not endure. A few examples of this sort may lead to an opinion, that "grafts, after some fifteen years, wear themselves out;" but the opinion is not (generally speaking) well founded. I have for many years grafted the old Golden Pippin on the Paradise or Doucin stock, and found it to answer very well, and produce excellent fruit. ”

“ The circumstances of Chaucer's life, his missions to Italy, during which he resided several months in that country, when sent on the king's business to Genoa, and Florence, and Lombardy, afforded {518} him ample opportunities of becoming thoroughly acquainted with the language and literature of Italy; the acquisition of which must have been of easy accomplishment to Chaucer, already familiar with Latin and French. ”

“ Cheap Portable Tent.—M. F. M. inquires for a cheap and portable tent for working collodion out of doors. I have been using one lately constructed on the principle of Francis's camera stand. It has a good size table, made like the rolling patent shutters; and it is not necessary to stoop, or sit down at your work, which is a great consideration on a hot day: you may get them of any respectable dealer in photographic apparatus; it is called Francis's Collodion Tent. ”

“ That sulphur is set free by the addition of an acid to the solution of hyposulphite of soda, is fact so easily demonstrable both to the eyes and nose of the operator, that no one need remain long in doubt who is desirous of trying the experiment. ”

“ This ends the piece.
"There is a plan, a progression, an intrigue, a catastrophe, and winding up; the style is good and well-supported; the thoughts and sentiments are all proportionate to the size of the personages. The verses even are short, and everything indicates pigmies.
"A gigantic puppet was requisite for Hercules; everything was well executed. The entertainment was productive of much pleasure; and I could lay a bet, that I am the only person who ever thought of executing the Bambocciata of Martelli."—Memoirs of Goldoni, translated by John Black, 2 vols., duod. vol. i. chap. 6. ”

“ Of course, for sharpness of outline he must be guided entirely by experiment in the camera; but where weakness of action exists, it most frequently arises from this yellow colouration, and which the manufacturers say is very difficult to avoid.
[Mr. Lyte having sent with his communication a positive prepared in the manner described, we are enabled to corroborate all he says as to the richness and beauty of its tints.] ”

“ From these circumstances, it was held most necessary that the digging of saltpetre and making of gunpowder should by all fit means be encouraged, at that time when it so much concerned the public safety; nevertheless, to prevent the reviving of those oppressions and exactions exercised upon the people, under the colourable authority of commissions granted to salt-peter-men ”

“ A correspondent desires to know how to test the coincidence or otherwise of the visual and actinic foci of a combination: this is very readily accomplished by the aid of a focimeter, which can be easily made thus:
Procure a piece of stout card-board, or thin wood covered with white paper, on which draw a considerable number of fine black lines, or cover it with some fine black net (what I believe the ladies call blond) , which may be pasted on. Cut up the whole into a dozen good-sized pieces of any convenient form, so that about four square inches of surface at least be allowed to each piece. ”

“ In reply to the question as to other modes of swearing, it may be said briefly, that men swore by anything to which they attached any importance, and generally by that to which they attached most importance. ”

“ I have in my possession a manuscript critique on the celebrated picture of The Last Supper by Lionardo da Vinci, written many years ago by a deceased academician; in which the writer has called in question the point of time usually supposed to have been selected by the celebrated Italian painter. ”

“ Next in point of time is a very singular memorial, which has evidently been removed from its original position, between the chapel and the high altar, to a situation at the south side and west end of the chapel.... The tomb is a messy frame-work of oak, with quarter-foils and arms on three sides, and on the table above three statues of the same material, namely, of a knight bare-headed, with rather youthful countenance and sharp features, and his two wives. ”

“ The cavalry gave them closs chase to the town of Inverness: {520} upon which the French ambassador (who is not well) sent out an officer, and a drum with him, offering to surrender at discretion; to which the duke made answer, that the French officers should be allowed to go about on their parole, and nothing taken from them. Brigadier Stapleton is among them, and God knows how many more officers; for we have not gote home to count them yet. ”

“ Proud Salopians.—I have never heard a satisfactory account of the origin of this title, given to persons belonging to my native county.
In the neighbourhood the following story is frequently related, but with what authority I cannot tell, viz. "That upon the king (Query which?) offering to make Shrewsbury a city, the inhabitants replied that they preferred its remaining the largest borough in England, rather than it should be the smallest city; their pride not allowing them to be small among the great." ”

“ Paste over the net a circular or square label about the size of a shilling, bearing a distinctly printed number one on each piece, from 1 upwards; and arrange the pieces in any convenient manner by means of wires inserted into a slip of wood; but they must be so placed that the whole can be seen from one point of view, although each piece must be placed so that it is one inch farther from the operator than the next lowest number. ”

“ He inclines to think that the studied diversity of expression, and the varied attitudes and gestures of the assembled party, are to be regarded as proofs of the artist's efforts to produce a powerful and harmonious composition, rather than a natural and truthful representation of any particular moment of the transaction depicted by him. ”

“ To the end there might not be any pretence to interrupt the work, it was ordained that the committee of safety, their factors, workmen, and servants, should have power and authority, (within prescribed hours) to search and dig for saltpetre in all pigeon-houses, stables, cellars, vaults, empty warehouses, and other outhouses, yards, and places likely to afford that earth. ”

“ I have myself for a long time been in the habit of using a weak solution of the protonitrate of iron in conjunction with acetic acid for positive pictures; for, although I do not consider it so good a developer as that made according to the formula of Dr. ”

“ Se buona, ond' è l' effetto aspro mortale?"
Petrarca, Rime in Vita di Laura, Son. cii.
"If no love is, O God, what feele I so?
And if love is, what thing and which is he?
If love be good, from whence cometh my wo?"
Troilus and Creseide, b. i.
Chaucer evidently had the following lines of the Paradiso in view when writing the invocation to the Virgin in The Second Nonnes Tale:
"Vergine Madre, figlia del tuo Figlio,
Umile e alta più che creatura,
Termine fisso d' eterno consiglio,
Tu se' colei, che l' umana Natura,
Nobilitasti sì, che il suo Fattore
Non disdegno di farsi sua fattura." ”