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larger, being not less than nine inches in clear aperture, the 

 largest ever made. The demand for such very large lenses, has 

 arisen from the desire for life size photographs, several of wliich 

 graced our exliibition at the crystal palace last autumn. The 

 cost of such large instruments must necessarily debar many 

 artists of small means from their use ; and this having been felt, 

 has awakened the inquiry, " how shall we execute these larger 

 pictui-es without the means to purchase the larger ajoparatus?" 

 But even with the largest apparatus, we cannot produce pictures 

 the size of life. And the special object of this paper is to explain 

 the best means of attaining that end. 



The Magic Lantern, once the plaything of our youthful days, 

 was brought out, but the light was found insufficient, and it was 

 returned to its resting-place. The Solar Microscope was then 

 taken up, it supplied the deficiency, and seemed the very thing 

 for the purpose. A negative collodion picture was put in the 

 place of the common slider, and a picture at once was impressed 

 upon the sensitive medium : it required a longer time of course, 

 to make a picture of sucli magnified dimensions; but as the object 

 could be kept still for any length of time, that was of little con- 

 sequence. But the lenses of the common solar microscope being 

 too small, larger ones were substituted, and thus full life-size pic- 

 tui-es were produced from the common size negative on glass ; 

 these were put into the hands of the painter, who, now having 

 something to work on besides a blank canvas, was enabled to 

 bring out a more correct likeness, and with greater rapidity, than 

 ever before : still the outline, even on this was not perfect, 

 although it answered the ends of the painter better than nothing; 

 and it is in this way the large full length portraits are made. 

 Having fitted up an apparatus for exhibiting these large pictures 

 to my friends, I was not a little mortified to find that my friend 

 Mr. A. B. Moore, a celebrated portrait-panter in this city, has 

 had a much better arrangement in use for a long time. We all 

 know that the magnified picture was never well defined. This 

 arose from one of those stubborn laws, well known to the optician, 

 the inflection of light, by which a pencil of rays, passing near an 

 opaque body, is deflected and dispersed. 



