17 



positive copies must be got by printing from it. Beautifully accu- 

 rate copies of a vast variety of objects may be procured in this 

 way. 



Some observations on this subject, which will be found under the 

 head of ENERGIATYPE, will perhaps assist the operator. 



ENERGIATYPE. 



The process which Mr. Huiit has designated the Energiatype, is 

 one of the simplest and most convenient modes of obtaining pho- 

 tographic pictures ; and the public are much indebted to this 

 gentleman for the prompt and handsome manner in which he 

 communicated his discovery, through the pages of the ' Atheneum.' 



"While pursuing," he says, " some investigations, with a view to 

 determine the influence of the solar rays upon precipitation, I 

 have been led to the discovery of a new photographic agent, which 

 can be employed in the preparation of paper, with a facility which 

 no other sensitive process possesses. Being desirous of affording 

 all the information I possibly can to those who are anxious to avail 

 themselves of the advantages offered by photography, I solicit a 

 little space in your columns for the purpose of publishing the par- 

 ticulars of this new process. All the photographic processes with 

 which we are at present acquainted, sufficiently sensitive for the 

 fixation of the images of the camera obscura, require the most 

 careful and precise manipulation ; consequently, those who are not 

 accustomed to the niceties of experimental pursuits, are frequently 

 annoyed by failures. The following statements will at once shew 

 the exceeding simplicity of the new discovery." 



Here follows, in the original letter, the description of the process 

 as then employed. We shall, however, introduce it to the ama- 

 teur with such modifications as the experience of Mr. Hunt 

 himself, and other gentlemen who have adopted the method, have 

 suggested to us. 



PREPARATION OF THE PAPER. Good letter paper, Whatman's, 

 or Moinier's pure white is best, is first washed over with the 

 following solution, viz. ; five grains succinic acid, dissolved in one 

 fluid ounce water, to which is added about fi ve grains common salt 



B 



