274 Dr. Hofmann on [May 16, 



to the security of the Bank. — There should also he a prima facie 

 security for the Public ; and if both are applied, they re-act upon 

 each other, and the Note is perfect. Some foreign Banks adopt 

 the plan of having different coloured papers for the notes of 

 different denominations of value ; how far this is an advisable 

 plan admits of question, for in addition to the fading of colour, 

 the circumstance of receiving a piece of coloured paper is apt to 

 induce a false security, assuming without inspection that the 

 document is of a certain supposed value. 



Having shown that production and reproduction react upon each 

 other, the question is, according to what plan the Bank Note should 

 be manufactured ? Let Art be impressed on the Note. — Let 

 ingenuity of design, executed by a hand whose genius would at 

 once indicate its authority, be adopted so far as is consistent with 

 a commercial purpose. — Let that mode of printing be employed 

 which alone can render the delicacy and force of an Art-subject. If 

 this course be followed, the greatest possible amount of difficulty 

 would be placed in the way of reproduction by hand; the two 

 scientific processes referred to cannot be brought to bear against it — 

 and further, which should be another grand object, this Art-education 

 of the people would eventually teach them prudence in distinguishing 

 the genuine from the false. Lastly, if this should eventually be 

 found insufficient to secure the desired result of unforgeability, 

 then it should be imperative on the Government to resolve this 

 question, and offer a reward, as has been done in other great public 

 questions, for its solution. 



[H. B.] 



WEEKLY EVENING MEETING, 



Friday, May 16. 



SiE Charles Fellows, Vice-President, in the Chair. 



Dr. a. W. Hofmann, F.R.S. 

 On the Chemical Type : Ammonia. 



The great laws which govern chemical combination, have been 

 mostly recognized and elaborated by the study of mineral compounds, 

 the examination of which at a very early period attracted the atten- 



