Home. Drawing Instruments. Slide Rules. Calculators. Miscellaneous. About Collecting. References. Links and Contacts. Technical Papers.
Other countries that made slide adders included the UK, France, Czechoslovakia, Japan, Hong Kong and the Soviet Union
Exactus Mini-Add
Exactus, London EC4, UK (made in England)
8 slides, 9 digit display; Sterling currency
Flip over front panel for subtraction
Aluminium & steel
4.5 x 3 inches
With wallet, stylus & instructions
1950s/1960s
Based on the Correntator
Machine à Calculer RéBo
Made in France
9 slides, 9 digit display
Brass & steel
6.3 x 3.5 inches
With wallet and stylus
1920s
RYCHLO POČTAŘ
Made in Czechoslovakia
8 slides, 9 digit display
Aluminium & steel
5.7 x 3.3 inches
With wallet and stylus
1930s
Obtained from the Czech Republic
Kingson Pocket Calculator
Empire made (Hong Kong)
Sterling currency version
6 slides, 6 digit display
Aluminium & steel
6.5 x 1.7 inches
With stylus
1950s/1960s
Kingson Pocket Calculator
Made in Hong Kong
6 slides, 6 digit display
Aluminium & steel
6.5 x 1.7 inches
With stylus & PVC sleeve
Table to convert fractions to decimals
1960s/1970s
Copy of Addiator Arithma
“Calculator”
Made in Japan
6 slides, 7 digit display
Metal & plastic
5.5 x 2.5 inches
1950s/1960s
Also sold as “Magic Brain” and “Taschenrechner”; 7 slide, 8 digit display version also made (see below)
Chadwick Magic Brain Calculator
Made in Japan
7 slides, 8 digit display
Metal & plastic
5.5 x 3.2 inches
1950s/1960s
Obtained from Canada
Winfield Pocket Calculator (sold by Woolworths)
Made in Hong Kong
6 slides, 6 digit display
Aluminium & steel
6.5 x 1.7 inches
With stylus, PVC sleeve, card box and instruction leaflet
Table to convert fractions to decimals
1960s/1970s
Identical to the Kingson except for the name (same manufacturer)
Copy of Addiator Arithma
Omega Pocket Adding Machine
Possibly made in Hong Kong (Construction same as Kingson except for width)
9 slides, 9 digit display
Aluminium & steel
6.5 x 2.3 inches
With stylus,
Table to convert fractions to decimals
Conversion table on rear from Imperial to Metric
Late 1960s
Copyright by T H Ramsey 1964
British Calculator (Model B) made by T J Marshall & Co, between 1905 & 1907. Serial no 1185 it has a faux Morocco covered case lined with blue velvet. The design was patented by H & M Dickinson in 1905, patent no GB12088A, and made from about 1905 to 1915. It was later labelled “BRICAL” as in the example below. It is 5.3 inches in diameter and reads £.s.d in halfpennies up to £499.19s.11½d. Because the £ scale only goes up to 49 there is a subsidiary window to the left that reads in steps of 50 from 0 to 450 that has to be added to the £ figure. I t has automatic carry over on all the scales.
Back to top.
Curta type 1 calculator serial no 12945 made in 1951 by Contina AG, Mauren, Liechtenstein. The reset ring has broken off and it is missing the three decimal point indicators from the top of the lower knurled ring. However it is still in good working order and can multiply, divide, add and subtract.

Business slide adder

Made in Belgium

6.2 x 4.8 inches

9 slides and 9 digit display

Wood and steel

Ca. 1926

Obtained from the Czech Republic

The “BRICAL” for Compound Addition. It has a padded, fitted, card case but still lined with blue velvet and blue silk. The case is entitled inside the lid and on top “The Brical Money Calculating Machine”. It is the same size as the calculator above but the construction is different. The pence and shilling scales are much extended and the pounds scale has 25 divisions exposed whilst the one above has twenty. However both work the same and the totaliser window in both reads in steps of £50. It has automatic carry over on all the scales. This is the later design and I don’t know why it was changed. The instrument is missing its styli of which there should be two. I believe these may have been ivory. Serial no A244.

Another version of the “BRICAL”. Instead of having a totaliser it has a fourth arc graduated in 50s from 50 to 1,000. It can add up to a maximum of £1,999.19s,11½d, quite a hefty sum in Edwardian times. Serial no B906.

Russian slide adder
6.5 x 1.7”
6 slides and 6 digit display
Steel
Steel stylus
Number 73 stamped on reverse
Obtained from Bulgaria
PICCOLO-S slide adder
6.2 x 1.7”
6 slides and 6 digit display
Aluminium & steel
Replacement stylus (ball-point pen refill)
Construction same as Kingson, etc
Olive/clear PVC sleeve
Obtained from Germany

This calculator is the same as the one above except that the title reads “The British Calculators Ltd BRICAL for Compound Addition PATENT” This has the same type of case as that below and one stylus (there should be two. It also has an outer card case. Serial no. 22284.

The British Calculator for Compound Addition model C It is for £sd and has a totaliser that increases in steps of £40. There is automatic carry-over. The cardboard case is covered in green cloth and lined with blue velvet and silk. It is fitted for the calculator. Serial no C299. This is a rare calculator made by British Calculators Ltd

“K” Accurator

Made in Hong Kong

6 slides, 6 digit display

Aluminium & steel

6.5 x 1.7 inches

With stylus & PVC sleeve

1960s/1970s

Identical to the Kingson except for the name (same manufacturer)

Copy of Addiator Arithma


Exactus Mini-Add

Exactus, London EC4, UK (made in England)

8 slides, 9 digit display; decimal version (scarcer)

Flip over front panel for subtraction

Aluminium & steel

4.2 x 3 inches

With stylus

1960s/1970s

Based on the Correntator