504 
Notes . 
undeveloped creatures ... is tlie precise counterpart of the 
forms of idolatry (expressed in the worship of unclean beasts) 
which were in great part the cause of final corruption in ancient 
mythology and morals.” 
We wish to call special attention to an Exhibition of applb 
ances, fuels, &c., for the prevention of smoke in dwelling-houses 
and factories, to be opened on October 24th, under the presidency 
of H.R.H. Prince Leopold, Duke of Albany. 
Mr. H. H. Howorth (“ Geological Magazine ”) argues that the 
circumstances under which the remains of the mammoth are 
found in Siberia, prove that these animals must have been 
destroyed by a great, sudden, and permanent fall of temperature. 
Prof. Hutchinson, in his Ledtures on the “ Laws of Inherit- 
ance in Relation to Disease,” mentions the fadt that colour- 
blindness is exceptionally common among Jews and Quakers. 
The “ Medical Press and Circular ” justly remarks that “ Of 
the rank and file of the aesthetic army, as of every hysterical 
school before, the majority are men of feeble intellectual deve- 
lopment, and women of that ultra-sympathetic type which is one 
of the forms of disease most prone to excite pity and disgust in 
the mind of the physician.” 
Prevention of Forgery . — In our February issue we gave an 
account of the safety-paper devised by Mr. A. Nesbitt, F.C.S., 
to prevent fraudulent alterations in cheques. We now learn that 
another process for the same objedt has been brought forward by 
Dr. Dupre and M. Hehner, who appear to be chemists to the firm 
of Charles Skipper and East, cheque-printers. These gentlemen 
propose to print upon the cheque a mixture of zinc sulphide and 
lead carbonate ; and they state that on treating the cheque with 
an acid or an alkali calculated to remove writing, double decom- 
position takes place, and the paper is darkened by the lead 
sulphide produced. This result undoubtedly happens with sul- 
phuric acid at certain strengths. But if the right degree be hit, 
as we have seen it experimentally proved, lead sulphate is pro- 
duced instead of sulphide, and the mixture and the paper to which 
it is applied remain white as before. Again, if alkaline solutions 
are used at random the mixture turns a brownish colour, and the 
attempt at fraud is betrayed. But if an alkaline solution is used 
of the proper strength, and containing a suitable proportion of 
sodium bicarbonate, the mixture of zinc sulphide and lead car- 
bonate remains perfectly v/hite, and the writing gradually disap- 
pears. Hence this invention would afford no protection against 
a clever forger, who would experiment till he had found the exadt 
strength of the solutions to discharge the writing without 
blackening the paper. 
