All these books, according to the good customs of several countries where I have been, should be taken and shown to a certain mercantile officer such as the Consuls in the City of Perosa employ, and to him you should state that those are the books in which you intend to write down, or somebody else write down for you, all your transactions, in an orderly way;  and also state in what kind of money the transactions therein should be entered – that is, whether in lire di Picioli, or in lire di Grossi, or in ducats and lire, etc., or in florins and denari, or in ounces, tari, grani, denari, etc.  The good merchant should put down these things always on the first page of his book, and if afterwards the handwriting should be done by somebody else than the one stated at the beginning of the book, this should be recorded at the office of the said officer.  The clerk should mention all this in the records of the said officer – that is, on such and such a day you presented such and such books, marked with such and such mark, which books are named, one so-and-so, the other so-and-so, etc; of which books one has so many pages, another so many, etc, which books you said would be kept by you or by so-and-so; but that it may be that in said Memorandum Book or Scrap Book or Blotter, some person of your family might enter said transaction, as explained before.  In this case, the said clerk shall write down on the first page of your books, in his own handwriting,the name of the said officer, and will attest to the truth of everything and shall attach the seal of that office to make the books authentic for any case in court when they might be produced.

This custom ought to be commended exceedingly; also the places where the custom is followed.  Many keep their books in duplicate.  They show one to the buyer and one to the seller, and this is very bad, because in this way they commit perjury.  By presenting said books to the said officer, one cannot easily lie or defraud.  These books, after they have been carefully marked and authenticated, shall be kept in the name of God in your own place, and you are then ready to start your business.  But first you shall enter in an orderly way in your Journal all the different items of Inventory in the way that I will tell you later.  But first you must understand how entries should be made in this Memorandum Book.