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d sold cameras fully equal to the German and for which Voitlander instruments have been refused in exchange by the purchaser。
The ordinary camera box （see fig。 5； a） varies in size to suit the tube； and is termed medium； half； or whole。 Within the box is a slide to assist in regulating the focus； and in enlarging or diminishing the picture。 In one end of this slide is a springed groove into which the ground…glass spectrum （g fig。 5） is slid； for the purpose of more conveniently arranging the focus。 After the plate is prepared it is placed in the holder partly seen at e； fig。 5； and covered with the dark slide f； fig。 5； the spectrum is then withdrawn and the holder takes its place； and the lids d； d； are closed after removing the dark slide f。 The plate is now ready to receive the image； and the cap c may be removed to admit the light into the box。
A camera constructed by Voitlander is thus described by Mr。 Fisher。 〃It is made entirely of brass； so that variations of climate has no effect upon it。 It is very portable and when packed in its box； with all the necessary apparatus and materials for practising the Daguerreotype art； occupies but very little space。 It is not； however； well adapted for the Calotype process。〃
〃The brass foot A （fig。 7。）； is placed on a table； or other firm support； and the pillar B。 screwed into it； the body of the camera； C； C is laid into the double forked bearing D。 D。 The instrument is now properly adjusted by means of the set screws； e； e； e； in the brass foot； or it may be raised； lowered； or moved； by the telescope stand； and when correct； fixed by the screw b。 The landscape to be delineated is viewed either through the ＇hipho_7。gif＇ small lens； g； or with the naked eye on the ground glass plate H； the focus being adjusted by the screw I。 The optical part of the instrument consist of the small set of achromatic lenses already described。 When the portrait or view is deleniated on the ground glass to the entire satisfaction of the operator； the brass cap L is placed over the lens； and the entire body is removed away into the dark； taking care not to disturb the position of the stand。 The body is now detached at the part H； and the prepared paper or plate enclosed in the brass frame work introduced in its place； the whole is again placed upon the pedestal； the brass cap L is removed； by which the paper or plate is exposed to the full influence of the light； after which the cap is again replaced。
Mr。 Woodbridge； of this city； has constructed an instrument for taking full length portraits on plates 10 by 13 inches； which is worthy of some notice。 It is a double camera； consisting of two boxes； placed in a frame； one above the other； and so arranged as to slide easily up and down。 After the focus has been adjusted； on the object； in both cameras； the plate is put into the upper box； in the manner already described； until the superior portion of the figure is complete； it is then placed in the second box and the lower extremities obtained。 The adjustment of the instrument is so complete that ＇hipho_8。gif＇ a perfect union of the parts is effected in the picture without the least possible line of demarkation being visible。 Fig。 8 gives a front view of this instrument。
Fig。 9 represents Talbot's Calotype Camera；a very beautiful instrument。
The copying camera box has an extra slide in the back end； by which it may be considerably lengthened at pleasure。
II。CAMERA STAND。The best constructed stands are made of maple or blackwallnut wood； having a cast iron socket （a； fig。 12；） through which the sliding rod b passes； and into which the legs c； c； with iron screw ferules are inserted。 The platform d is made of two pieces； hinged together； as at e； and having a thumb screw for the purpose of elevating or depressing the instrument。 ＇hipho_9。gif＇
III。 MERCURY BATH。Fig。 13 gives a front view of the mercury bath now in general use in this country for mercurializing and bringing out the picture。 It is quite an improvement on those first used。 To make it more portable it is in three pieces； a b and c； having a groove e on one side to receive the thermometre tube and scale by which the proper degree of heating the mercury is ascertained。 Into the top are nicely fitted two or three iron frames； with shoulders； for the plate to rest in； suitable for the different sizes of plates。 The bath is heated by means of a spirit lamp placed under it。 From two to four ounces of highly purified mercury are put into the bath at a time。
IV。 PLATE BLOCKS AND VICES。There are several kinds of this article in use； I shall describe the two best only。
Fig。 10 gives an idea of the improvement on the English hand block。 The top a is perfectly flat ＇hipho_10。gif＇ and smootha little smaller than the plate； so as to permit the latter to project a very little all aroundhaving at opposite angles c c two clasps； one fixed the other moveable； but capable of being fastened by the thumb screw d； so as to secure the plate tightly upon the block。 This block turns upon a swivle； b； which is attached to the table by the screw c； This block is only used for holding the plate while undergoing the first operation in cleaning。 ＇hipho_11。gif＇
Fig。 11； shows the form of Lewis' newly patented plate vice； which for durability； simplicity and utility is preferable to all others。 It consists of a simple platform and arm of cast iron； the former； a； having a groove； d； in the centre for fixing the different sizes of plate beds； eand the latter supporting the leaves； e f。 On this vice which is secured to a table； or bench； the plate receives its finishing polish with rouge； or prepared lampblack。 Mr。 Lewis gives the following directions for its use。 〃As the cam wears tighten it with the adjusting screw （g） so as to allow the lever （f） to fall back into a horizontal position； the plate being in its place at the time。 Oil the wearing parts occasionally。〃
Some Daguerreotypists； however； use a foot lathe with buff wheels of various forms； but this vice is sufficient for all ordinary purposes。
V。 COATING BOXES。The usual form for iodine and ＇hipho_12。gif＇ ＇hipho_13。gif＇ bromine boxes is see； at figs。 14 and 15。 They are far superior to those in use with the English operators。 Each consists of a wooden box （a；） having firmly embeded within it a stout glass jar （c）； the edges of which are ground。 Over this is placed the sliding cover b； double the length of the box； one half occupied by a piece of ground glass （e）； tightly pressed upon the glass pot by a spring （i） beneath the cross bar g； and fits the pot so accurately that it effectually prevents the escape of the vapor of the iodine； bromine or other accelerating liquid contained therein。 The other half of the lid is cut through； shoulders being left at the four angles for the different sizes of frames； designed to recieve the plate while undergoing the coating process。 When the plate is put into the frame； the cover b is shoved under the second lid h and when coated to the proper degree； it resumes its former position and the plate is placed in the holder of the camera box。 To test the tightness of the box； light a piece of paper； put it into the pot and cover it with the sliding lid。 The burning paper expels the air from the pot； and if it be perfectly tight you may raise the whole box by the lid。
VI。 GLASS FUNNELS。Are a necessary article to the Daguerreotypist； for filtering water； solutions； &c。 ＇hipho_14。gif＇
VII。 GILDING STAND。For nervous persons the gilding stand is a useful article。 It is adjusted to a perfect level by thumb screws placed in its base。
VIII。 SPIRIT LAMPS。The most useful and economical of those made are the Britania； as they are less liable to break； and the tube for the wick being fastened to the body by a screw renders it less liable to get out of order or explode。 Glass is the cheapest； and for an amateur will do very well； but for a professed artist the Britania should always be obtained。
IX。 COLOR BOX。These are generally found on sale at the shops； and usually contain eight colors； four brushes and a gold cup。 The artist would； however； do well to obtain； all the colors mentioned in the last chapter of this work； and be sure to get the very best； as there are various qualities of the same color； particularly carmine； which is very expensive； and the cupidity of some may induce them to sell a poor article for the sake of larger profits。 ＇hipho_15。gif＇
STILL。Daguerreotypists should always use distilled water for solutions； and washing the plate； as common water holds various substances in solution which detract very materially from the excellence of a photograph； and often gives much trouble； quite unaccountable to many。 For the purpose of distilling water the apparatus represented at Fig。 16 is both convenient and economical。
It may be either wholly of good stout tin； or of sheet iron tinned on the inside； and may be used over a common fire； or on a stove。 A is the body； which may be made to hold from one to four gallons of water； which is introduced at the opening b； which is then stopped by a cork。 The tube d connects the neck a of the still with the worm tub； or refrigerator B； at e； which is kept filled with cold water by m