THE PREVENTION OF FORGERY.

Globe, Volume XXII, Issue 1936, 8 May 1880, Page 4

THE PREVENTION OF FORGERY.

Mi H. Bessemer writes as follows to the “ Times ” with reference to its statement that “ an official of the Bank of England has made experiments with the chemical preparation described in the recipe, and ho has stated that it takes out the writing on a cheque without »ny apparent stain —The only wonder is that it should have been reserved for Mr W. Walter to avail himself of a fact which is equally well khown to thousands of other persons. To the calico printer the art of discharging the fastest colors and leaving the fabric colorless at any desired spot is simply a part of his every-day employment. Many of your readers will doubtless remember the Canary and Indian-red silk handkerchiefs so fashionable thirty years ago, which were dyed all over of one color ; now, all the white spots or oth. r patterns were formed on them simply by applying with a block a solution of . ... which effectually removed every trace of the fast dyes from those parts of the fabric with which it came in contact. Enough of this simple chemical can be purchased at any chemist’s shop in London for 3d to take out all the writing from a hundred or two of cheques. Hence everyone will agree with you that “ all this is not reassuring to people who have banking accounts and who daily write cheques.” It may, therefore, interest many of your readers to know that an absolute bar to this species of fraud is within our reach, without involving any extra trouble, and at a very trifling cost. About the year 1833, when I was deeply engaged with plans for preventing the forgery of stamps, bank-notes, and other securities, I proposed a very simple mode of preventing any alteration of the writing in cheques and other written documents by means of chemicals. The plan was simply this : —I take any pale vegetable color, say blue, which should be as sensitive to acid reaction as litmus, and with this color I print over the whole surface of the cheque or other paper a line engine-turned pattern, thus giving to its surface somewhat the effect of a pale tint extending all over the paper, and which in no way interferes with any black printing or writing that may afterwards bo put thereon. Such paper may be produced cheaply by the ream, and be used for cheques and other purposes whore it is desirable to prevent any tampering with whatever may be written thereon. Now, if any attempt should bo made by means of chemicals to take out any portion of the writing on such prepared paper, all the surrounding parts touched by the acid solution will at once lose the whole of the blue printed pattern, which is more sensitive and much more easily discharged than the common writing ink sought to be got rid of, and would thus leave a white patch where all the delicate tracery of the blue pattern would be absent, and consequently the cheque with these evidences of the attempt to alter it would itself become valulesa, and the would-be-forger would simply lose the amount of the cheque he had spoiled. The old trick of altering the words six, seven, eight, and nine by the mere addition of the letters t and y, and thus increasing the value to sixty, seventy, eighty, and ninety, would become impossible if the

cheque had the word “units” printed in large pale-colored letters extending across it, such cheques being reserved for sums under £lO.