28 BOOK'S OF SECRETS. 



A noticeable feature of these books is the constancy with which the 

 receipts both for medicine and for everyday wants are repeated without 

 alteration in one edition after another. Apparently, the secrets gained in 

 authority by repetition, and if they had stood the test of time and had 

 yielded the expected result, there was no reason why they should be 

 changed or superseded. 



As instances of receipt books concerned with one topic only, examples 

 may be selected again from the Italian. 



One is upon dyeing, and is entitled : " Plictho, or the art of the dyer, 

 how to dye wool, silk, linnen." It was written by Gioanventura Rosetti 

 and published at Venice in 1540. It forms a thin small quarto of forty- 

 four leaves, and contains one or two woodcuts depicting parts of the 

 process. This is a collection of dyers' receipts and methods ; it describes 

 the quantity of the substances required, the length of time the fabric is to 

 be immersed in the colour bath and the whole treatment. The art of 

 dyeing is of great antiquity and the use of mordants to make colours fast, 

 for example, must have been known at an early period. Of this book 

 there were at least five editions, the first of 1540 already mentioned, the 

 fourth at Venice in 161 1, and the fifth in 1672, with some changes and 

 additions, but even with these, one hundred and thirty years is a good life 

 for such a book. Modern technical books are much more short-lived. 



When engaged with dyeing one must not overlook receipts for making 

 inks and colours, for taking out spots and stains and for colouring wood, 

 bone, and feathers. These are chemical applications and as such I have 

 described them in a series of papers still in progress.' The earliest 

 collections of these receipts which I have seen are in German and of date 

 1 53 1, in following years tracts of similar character were associated with 

 them and translations of them were made. I have seen some fifty editions 

 of these books, but from internal evidence it is probable that that number 



(i) Proceedings of the Royal Philosophical Society of Glasgow, from 1888 to 1913. 



