Roberval balance
![This sketch shows a Roberval balance with balanced masses. Note that the masses don't need to be centered on the plates.](/Images/godic/202502/07/Roberval_balance5230.jpg")
![Old Roberval balance](/Images/godic/202502/07/Roberval_scale5230.jpg")
![Roberval balance made by W & T Avery Ltd. in England](/Images/godic/202502/07/Balance_Roberval_white5231.jpg")
![Another example: note that the bottom horizontal beam is hidden under the protective cover](/Images/godic/202502/07/Balance_Roberval_detail5231.jpg")
The Roberval balance is a weighing scale presented to the French Academy of Sciences by the French mathematician Gilles Personne de Roberval in 1669.
In this scale, two identical horizontal beams are attached, one directly above the other, to a vertical column, which is attached to a stable base. On each side, both horizontal beams are attached to a vertical beam. The six attachment points are pivots. Two horizontal plates, suitable for placing objects to be weighed, are fixed to the top of the two vertical beams. An arrow on the lower horizontal beam (and perpendicular to it) and a mark on the vertical column may be added to aid in leveling the scale.