BECKER'S  SONS - ROTTERDAM
letter scale

letter balance, maker Becker's Sons Rotterdam

This balance made by Becker's Sons, Rotterdam is a postal balance. In 1914 the company moved its headquarters from Rotterdam to Brummen in the province of Gelderland. This letter scale is described in a Becker's Sons catalog of approximately 1911. The three rows of weights (4 + 4 + 3) are also recognizable in the image from the catalog. As one can read in the catalog, the letter scale is "exclusively used by the Mail Administration" (in Dutch: 'uitsluitend in gebruik bij de Administratie der Posterijen'. There exists also a version suitable up to one kilogram. I know of a same balance scale with the name Landre & Glinderman Amsterdam on the balance beam. In that letter scale the weights are in two rows (7 + 4).

weighing range 500 grams

The Becker's Sons shown here has the following weights: 1 x 1g, 2 x 2g, 1 x 5g. 2 x 10g, 1 x 20g, 1x 50g 2 x 100g and 200g. Together that makes 500 grams. The letter scale presented here, was restored by J.S. Velthoen & Zn., Rotterdam-Schiedam in 1956, according to the little plaque attached on the wooden base. In this revision an ugly plastic spirit level was applied and three separately adjustable heavy duty feet were added below and partly in the wooden base. After this restoration the balance was approved individually again, the crown in the brass base of the stand is the sign of this approval. The inspection was done at the calibration office (in Dutch: ijkkantoor) number 6, which is in Rotterdam. Over time the plastic spirit level became empty. In 2006 I have replaced that plastic spirit level by a brass spirit level from another PTT letter scale of J.S. Velthoen & Zn. As shown on the detail picture, this spirit level unfortunately has a small black spot, the leveling is not prevented by this. The letter scale is leveled by turning the three sturdy set screws. The bubble of the spirit level is thereby centered in the inner ring on the glass part. The balance can then be fine tuned in perfect equilibrium at the right side of the balance beam by turning the adjustment nut. Then the indicator points out in the middle of the little ivory scale at the stand. Of the letter scale model with the two weight rows generic specimen exist also, i.e. no name, no brand.

as pictured in the Becker's Sons catalog of approximately 1911

rear of the balance

testimony plate as to proof of the restoration by J.S. Velthoen & Zn

top view	scale beam	the balance arms
BECKER'S SONS	ROTTERDAM	500 g
the factory mark for the detachable parts left = 2 points	knife edge bearing left	knife edge bearing left
the adjusting nut at the right	knife edge bearing right	the factory mark for the detachable parts right = 1 point
the main knife edge of the beam	pointer from behind	detail of knife edge support
brass bearing block for main knife edge	bearing block for main knife edge	the lock nut of the pointer
left pan	frontal view pointer	right scale
top view left pan	frontal view	the curved right scale
3 rows of slots for the weights	the eleven weights in front of the scale	the eleven weights placed in the slots
calibration office 6 = Rotterdam mark of individually approval = crown	the spirit level	detail of the foot of the stand
the eleven weights	the central zone	the eleven weights
the eleven weights	the eleven weights	spirit level behind the weights
brass bracket for adjustable leg	the two-piece adjustable leg	mounted two-piece adjustable leg
The three adjustable feet in the picture	both pans removed	the beam lifted from the stand