1096 TSAtrSACTIONS OF THE AUERIOAX ImTITVTM. 



line by the addition of canrtic potash; he then exposed it to «m. 

 tlZ ' "'* """^ ™-^ ^'""'^^ '0 '"-^ -'^i^-'"' b^' Mr. 



Mr. Daniel Chapman said he had used oxjd of silver and coneen- 

 trated ammon.a m his bath solution, and after exposure to iZL 

 weeks, found it capable of most excellent results ° 



trabJ:^^^^*'™'*'*'"^ "'"' ^^ ^^ "^^'^ "^3'd of silver to ne». 

 rahze the free mtnc acid in the crystals of silver, and then used 

 cyamde of potassium in sufficient quantity to produce alkaline reac- 

 tion He exposed the solution to sunlight on the 2Sth of June last 

 and had not yet taken it in for trial. ' 



6u Jel"?'""'' ''"^ "''"' "■'"'""^ *°'" ^"'^'^'^' "^anderweyde on this 

 Each member of the committee working independentlr, and by 



tha "^^ mT' m ^"'!,""''^' results, seems to warrant a conclusion 

 tha Mr. McLochlan's discovery is an important one, and worthy of 

 trial by all photographers. ' 



of ^hif^' I' ^T^r^ 'f """'"^ " ""'^ ^°^ "''S"*'™' " 'h^ production 

 ot which he had used a bath rendered alkaline by the addition of 

 ^anide o^potassinm and then exposed it to sunlight about ten hours. 

 He also stated that he had used nitrate of ammonia in his sensitizing 

 bath for glass positives, and found that it enabled him to produce 

 greater harmony and more delicate details, besides renderin- the 



" o Th ?: T'T:"""-^' - ''^ -'^g ^-lities. Mr. Anthony 

 Jso exhibited and donated to the section a series of stereographs 



acMT^H^' .T ;■ '" "''"' '^ "'"'^ " ^■"^'^-"' quantity of citric 

 acnl to redden blue litmus paper, and afterward added carbonate of 



oda until the blue color of the paper was resto..d ; in which state 

 thesolution has a slightly milky appearance, which Mr. Anthony 

 believes to be caused by the liberation of sulphur which is held in 

 suspension. 



By request of Mr. Anthony the prints were dated and placed in 

 the cabme for future reference as to their permanency. He 

 expressed: his belief that they would not change 



K. ♦ °,- ^^P'""" ^^'1 ^' had, in his solar printing produced the 

 best results by using old solutions of hyposulphite of soda for fixing 

 and he usual y added a portion of old solution whenever he prepared 

 anew: iixmg. bath, r r '-'* 



