290 



NOTES AND QUERIES. 



[No. 285. 



CeroUine on Paper. — 1. If the paper is thin, take 250 

 grammes of solution of ceroleine, 6 grammes of pulverised 

 iodide of potassium, 1 grain of bromide of potassium, 

 1 drop of tincture of iodine. 2. If the paper is thick, 

 take 250 grains of solution of ceroleine, 4 grains of pul- 

 verised iodide of potassium, 50 centigrammes of bromide 

 of potassium; mix them together and assist their com- 

 plete solution, then filter them with care. Iodide of zinc 

 may be, perhaps, advantageoush' substituted for iodide of 

 potassium, when the high temperature obliges us to 

 augment the quantity of the sensitising agents. The 

 addition of 1 gramme of cyanide of iodine and silver 

 increases the action of the light very much, but the sen- 

 sitised paper keeps a shorter time when dry. Passed 

 through a batli and dried, the paper may be preserved 

 indefinitely, and becomes better for keeping. When it 

 is employed it should be placed in a silver bath, formed 

 of distilled water 100 grammes, fused nitrate of silver 

 5 grammes, crystallisable acetic acid 12 grammes. In 

 the bath the paper becomes of a very uniform yellowish 

 white tint ; when it is taken out and held up tothe light 

 it no longer shows any mark. If it is wished to work by 

 the wet process, the paper taken out of the bath should 

 be simply stretched (carefully avoiding any bubbles of 

 air) on a glass already covered with unsized paper, well 

 wetted, and it should be placed on the glass so covered in 

 the frame for placing in the camera. 



If it is wished to work by the dry process, we proceed 

 as follows : after taking the paper out of the silver bath, 

 wash it rapidly (at least if it is not very thin) in distilled 

 water, acidulated with acetic acid, and suspend it (without 

 attempting to remove the water) by a corner to dry. 

 When you have prepared and dried the number of papers 

 you want, put them between the leaves of a portfolio of 

 blotting-paper, separated from one another. We can thus, 

 before the paper is completely dry, lay it upon a glass, or 

 waxed or varnished pasteboard, or in" fact on a small var- 

 nished board, pasting it with strong paste at the edges. 

 In drying the paper contracts, becomes stretched, and has 

 a very smooth surface, which can easily be placed in the 

 focus, and will receive an image with great clearness. 

 The time of exposure varies from one minute to three 

 quarters of an hour, and must be determined by experi- 

 ment. Before placing the proof in gallic acid", in order 

 that it may imbibe it, wash it, and let it be thoroughlv 

 saturated in a bath of distilled water ; let it imbibe slowlj"', 

 without adding nitrate of silver too soon. The time 

 necessarj' to the perfect development varies, according to 

 the time of exposure, from two minutes to three quarters 

 of an hour. After taking the proof out of the gallic acid, 

 wash it well and fix it in the following bath ; hyposul- 

 phate of soda 100 grammes, filtered water 1000 gr'ammes. 

 Let the proof become perfectly white in the light parts ; 

 wash it again during seven or eight hours, changing the 

 water frequently; drj^it completely, and, if itis necessary, 

 •wax the proof to render it transparent. 



Stkphane Geoffray. 



Eoanne. 



Camera for Preserved Sensitized Plates, Sfc. — I am 

 sorry to find that I should have plagiarised Mr. Mer- 

 ritt's camera in the one I have described in " N. & Q.," 

 Vol. xi., p. 191. ; and at the same time I must ask Mr. 

 Merrii"! to forgive the mistake I have thus made, as it 

 has only arisen from my absence from England having 

 prevented me from becoming acquainted with anj'thing 

 but the name of Mr. Merritt's invention, and I am quite 

 willing to cede to him all claim to priority. I have 

 lately made a slight alteration for convenience sake in 

 my camera, which is as follows : instead of the arrange- 

 ment I mentioned, I have again substituted the use of the 



dark slider in which to keep the plate, and I have a box 

 for the prepared plates, which has grooves carrying small 

 planks of wood, on each of which is fixed the prepared 

 plate, and each of which fits into and forms the back of 

 the dark slide. Then I have a sack of 3'ellow calico which 

 goes over the head and fits round the waist as recom- 

 mended by Dr. Diamond, and in this I perform all the 

 operations of changing the plates. This arrangement I 

 find much more convenient, as being less liable to de- 

 rangement on account of its simplicitj', — a grand deside- 

 ratum in photographic instruments. The little planks of 

 wood are made with two little crotchets of silver at one 

 end, under which to pass one end of the plate, and two 

 little buttons of silver at the opposite end which hold 

 the other end of the plate, and four little pegs of ivory, 

 two on each side, to prevent the plate moving sidewaj's, 

 and a spring in the centre of the plank to press the plate 

 outwards against the crotchets, which ensures the face of 

 the plate being always in the same place whether the 

 glass be thick or thin. I have also to communicate to 

 you a method by which I can preserve the collodion plate 

 quite dry, viz. by making a syrup of white dextrine, and 

 adding to it just enough grape sugar or honey to prevent 

 it from cracking, which will be found upon drj-ing some 

 of it on a bit of glass ; replacing the ordinary syrup, 

 which I have before indicated, with this; and letting the 

 plate drain dry, and for the after treatment soaking the 

 plate as usual to get rid of the substance from its surface 

 before development. Attention must be given to wash 

 the plate long and well in this way, as on this depends 

 much of the success of the operation. I doubt not that 

 the steaming of Dk. Mansell will prove most excellent, 

 and much wish he would tell us what is his manner of 

 applying it, as I have tried it, but have not been so suc- 

 cessful as in ordinary and very prolonged washing. I 

 have tried gum arable for preserving the plates dry 

 in the above manner, but find dextrine on the whole 

 more successful. The syrup need not be very thick for 

 the above purpose, and may be thinned at almost the 

 will of the operator, until it" flows evenly and easily. I 

 hope in the course of next week to follow this up with a 

 perfectly explicit detail of the best way of making the 

 dextrine for this purpose ; but with the details I have now 

 given, I feel no doubt any operator will easily succeed, as 

 dextrine of first-rate quality is to be found at most good 

 chemists in London. ' F, Maxwell Lyte. 



Pau, April 3, 1855. 



»rjjltcs to ^Cnor (ikueviei. 



Cothon (Vol. xi., p. 207.). — It appears to me 

 probable that this word, as signifying an artificial 

 harbour, may be derived from the Greek Kcieccv, a 

 Lacedasmonian cup, made of iron, and much used 

 on shipboard. In the Equites, Aristophanes in- 

 troduces the chorus of knights praising their 

 horses (symbolising themselves), and declaring 

 that 



"....• 'E? Tas InnoLyiayovi ei<re5r^5wf ai'Spi(c(09, 

 Hpiau.ei'Oi KiaOiava^," k. t. A. 



innEIS, lines 581, 582., Mitchell's edit. 



Perhaps the use of such an article at sea may 

 have suggested the application of its name to an 

 artificial port or harbour, such as we should now, 

 I believe, call a "basin." 



Francis John Scott, M.A. 



Tewkesbury, 



