Book with numbers and advertising therefor

Numbers - a book full of them.

This is a book full of multiplications, one large table.  It was advertised for in a technical handbook shown below. This was aimed at engineering students (MTS students; Middelbare Technische School), for the year 39-40, and itself is filled with mathematical and technical information as wel as practical information on many technical components of the day. 

Amongst the several sponsored sections and adverts for all the things a starting engineer or machinist might need, here is the one for a calculating- or arithmetic-dictionary, the Rekendictionnaire by W. Vriesendorp.

The advertisement clearly explains what it is; a bound book with all multiplications of 1 to 999 by 1 to 999. A quote of an NRC newspaper review: "Het geheel is het product van een merkwaardig geduld en nauwgezetheid..." - The work is the product of a curious patience and scrupulousness. The line is hard to translate, but is neatly phrasing it as a product (i.e. a multiplication result) and might have a hint of irony, perhaps sarcasm?

That did not however deter Vriesendorp from using the quote in advertising his book of tables.

(The ad on the other page recommends spending a few Guilders more for the quality of a Richter drawing set - recently did :-)

Such books of mathematical tables were fairly common, every region or country having its own variant. Mathematical tables 'proper' would at least have a table of logarithms. These simple books with multiplication-tables are a bit of a 'subset' of the category; but multiplication-tables still had a market and use however, even when the 'proper' books of tables were already largely displaced by sliderule or calculator.

(Advertising in a technical handbook might seem logical at first sight, however for the technical audience almost all calculations can be done with a sliderule - rarely needing nore than 3 digits significance. But in tallying partslists, extending bills etc, there might be a need.)

So a multiplication-tables only book, and only for the Dutch market, the Rekendictionnaire can still be found for sale second-hand:

It is indeed a hefty, bound book about A4-page size weiging in at almost 2 kilos. Published in 1937, it claims to contain 'tables' - or rather, it contains one large table.

In one page is the foreword and the full instructions on how to use the book to do multiplications. Not just of numbers up to 999, but also how to break-up problems to be able to do larger products. There would have been a loose-leaf insert with more examples, that sheet was however missing in this specimen.

The book itself is then pages full of numbers (quite the nightmare to set and proofread, I imagine). 

The numbers 0 to 9 are printed on the side to assist in opening it near the right number.

The book does not reduce the duplicates, i.e. it contains the answer for 28 by 231 both on the page of 28 (6468) as well as for 231 by 28 on the pages of 231 (6468). 

Looking up an answer is pretty easy; finding for example the product of 495 and 617. On the page of 495, look in the 600s column and find in the 10s row the answer 305415 printed behind 617.

Doing a quick check on a contemporary ~1940 pinwheel calculator; it of course arrives at the same answer :) 

The book is less capable than the calculator, but at Hfl 12,50 it only cost a small fraction of the price of a calculator that would have cost several hundred. As a way to do multiplications rapidly with a precision of more than 3 digits (sliderule), this book could have seemed an attractive solution.