CONCAV
letter scale

This letter scale is made by Philipp Jakob Maul. The M-logo is engraved in the left brass strip of the mechanism of the scale. The scale is severely corroded: especially the plate has many spots. The chart and also the frame are severely corroded also. The light weight frame is made of folded tin. The range is 250 grams. Per 5 grams a division stripe is given. The scale is placed concav thus improving the readability. The realised direction of reading the scale is logical:  from left to right. This design exists also in a version with a range of 100 grams, see the little concav scale. The mechanism of this 100 grams version is not made of brass but of chromed tin. The 500 grams version has a more solid base made of steel strip, see for instance the concav with met aluminum bowl. The letter scale has a zero adjusting screw. Below some more photos of this little scale.