512 



NOTES AND QUERIES. 



[No. 296. 



care to place them at a j>roper distance, according to their 

 size. The distance of one gia.-s from another should be 

 five centimetres for glasses of twenty-seven by twenty- 

 one ; it should be double for glasses of twice the size ; the 

 maximum temperature of the place where tliey are dried 

 should not exceed eighteen degrees centigrade (65"2 Fah- 

 renheit). At this temperature the glasses are dried in 

 about twelve hours. They may be prepared in the even- 

 ing for use on the following day. 



"Silver Bath.— 



Distilled water - - - - 100 grammes. 

 Nitrate of silver - - - 10 grammes. 



Acetic acid - - - - 10 grammes. 



Proceed as for collodion. The albumenized glass should 

 remain one minute in the bath. It is then placed in a 

 trough filled with distilled or rain water, where it is left 

 until another glass has been treated in the nitrate-of- 

 silver bath. It is then placed on a stand and washed 

 with distilled or rain water. 



"The glasses, after preparation in the nitrate-of-silver 

 bath, will keep for a fortnight in summer. In order to 

 keep them longer one must be laid upon another, the 

 albumenized sides touching, and a slip of paper pasted at 

 the edges, to prevent the action of the air. 



"JExposure in the Camera. — The exposure should be re- 

 gulated by the length of the focus of the lens, in sunlight 

 one minute for every inch of focus ; it should be at least 

 twice as long in the shade. 



"Developing the Image. — Pour upon the glass a solution 

 of concentrated gallic acid. As soon as the image ap- 

 pears throw this solution away, and pour on a fresh one 

 containing a small quantity of nitrate of silver, but no 

 acetic acid, and the image will be developed in half an 

 hour. If the time of exposure has been properly calcu- 

 lated it will appear immediately, but if the exposure has 

 been too short it will not appear in less. Instead of half 

 to three quarters of an hour, it sometimes requires twelve 

 or fifteen hours. It is washed with common water before 

 fixing. 



"Fixing the Picture. — Merely washing with 100 grammes 

 of water, containing ten grammes of hyposulphite of soda, 

 suffices to fix it. 



" In answer to a question j M. Fortier stated that he 

 dissolved the iodide of potassium in pure albumen ; never- 

 theless the solution may be hastened by adding a small 

 quantity of water. He deprecated the use of cyanide of 

 potassium for fixing, as it detaches the albumen from the 

 glass. This fact can be made use of in cleaning the albu- 

 menized glasses. The plate is covered with a solution of 

 cyanide of potassium : after a minute the glass is thrown 

 into water, and the albumen is removed. 



" Upon a question being put to him as to accelerating 

 substances, M. Fortier said that honey, as well as syrup 

 of honey, added to the silver bath, augments the sensi- 

 bility, but rapidly undergoes alteration. As to fluoride of 

 potassium, it gives great sensibility. Its employment 

 admits also of portraits being taken on albumen ; but in 

 drving the glass the albumen detaches itself, curling up 

 in spirals. With regard to the time after exposure within 

 which the image may be developed, M. Fortier said that 

 he had never deferred it more than a day, but that this 

 delay was not productive of any inconvenience." 



Mounting Photographs. — With reference to this subject, 

 which has excited some interest, from its supposed con- 

 nexion with the fading of positives either through the 

 agency of the material used for mounting them, or the 

 chemical constituents of the paper or Bristol board to 

 which they are attached, a correspondent suggests that 



no better adhesive medium will be found than simple 

 albumen, or white of egg. If applied to the back of the 

 positive it will not only cause it to adhere evenly and 

 firmly, but from its very nature acts as a protective from 

 the deleterious influence of the chlorides in the paper or 

 cardboard on which it is mounted. 



^tpXiti to Minav ^xttviti. 



Dr. Houth (Vol. xi., p. 61.). — I observe that the 

 late President of Magdalen's works extend over 

 a period of sixty-nine years (1784 to 1853). Is 

 there any other author of ancient or modern times 

 that can equal this ? The nearest approach to it 

 that I can remember is Ruysch, a Dutch anato- 

 mist, whose publications included the space of 

 sixty-five years from first to last. J. S. Warden. 



Artificial Teeth (Vol. xi., pp.264. 395.). — A 

 correspondent inquires, " what is the date of the 

 introduction of artificial teeth into England or 

 Europe?" To this Query there is an authority 

 quoted (p. 395.), showing that they were not un- 

 common in the reign of James I. (anno 1609) in 

 England. But that this substitute for nature's 

 decay was usual in the days of the Koman Em- 

 perors is confirmed by a caustic epigram of a 

 witty poet : 



" Thais habet nigros, niveos Lecania dentes ; 

 Quas ratio est ? emptos haec habet, ilia sues." 



Martial, Epig. V. 43. 



C. H. 



Ritual of Holy Confirmation (Vol. xi., p. 342.). 

 — The Confirmation service, translated into Latin 

 and Greek, may be found in — 



" Preces Catechismus et Hymni Graece et Latine in 

 vsvm Antiqvae et Celebris Scholae jvxta S. Pavli : Tem- 

 plvm apvd Londinates venerabili admodvm viri Johanna 

 Coleto, S. T. P. Necnon S. P. Decano, Londini, 1814, 

 Bagster, 1852," &c. &c., 8vo. 



Privately printed. A copy is now given to each 

 scholar on his entrance to the school. E. W. O. 

 Camberwell. 



Ancient Libraries (Vol. xi., p. 258.). — 

 "The Gray Friers have a library in their house, in 

 Roane, containing six-and-fifty paces in length, with 

 three rowes of deskes all along, replenished with many 

 excellent bookes both of philosophy and the Fathers, the 

 most part manuscript." — Stow, Annals, 1632,. fol., p. 778. 

 coL 1. 1. 40. sub an. 15i)6. 



E. W. O. 



Camberwell. 



Query for Naturalists (Vol. xi., p. 408.).— 

 Three years ago I had in my care a female parrot, 



the property of my friend Mr. S . It was a 



common green parrot, a poor talker, a female, and 

 very aged. It evinced the same hatred for its sex 

 in the" human species as the one mentioned by 

 R. W. D.— Jp. When in its cage, it would 



