FIELD: chronology engineering.
SUBSTANCE: device has Orthodox Easter date scale and two rotatable disks having marks and mounted on axle. The marks are available at intersection points belonging to 35 concentric circles which centers coincide with disk axle center. 28 rays are available on the first disk and 19 on the other one. The disks are fabricated as gears having teeth number equal to the number of rays. Teeth peaks are placed in points of disk rays and disk boundary intersection. The Orthodox Easter date scale is arranged in parallel to along the line of one of the disk rays. The disk marks and Orthodox Easter dates are in appropriate points of disk rays and concentric circles intersection and in appropriate positions on the Orthodox Easter dates scale determined from table. Another device version additionally has disk having the Orthodox Easter dates scale and the Orthodox holy days dates scales. The disk is transparent or has slits along the Orthodox Easter dates scale or Orthodox holy days date scales.
EFFECT: high accuracy and simplicity in use.
13 cl, 4 dwg, 3 tbl
