Plastic disc with moving inner wheel"GESTATIONAL CALCULATOR" "DOWN BROS and MAYER & PHELPS LTD" "GESTATION PERIOD IN WEEKS" on reverse side; "NESTLE LACTOGEN"pregnancy calender, gestational calculator

A reference guide of 32 pages plus cardboard covers. The volume has wire spiral binding. It includes a perpetual calendar. Other pages include tables, charts, dates, mathematical information and useful information for farmers including weights and measures and animal gestation periods.A ready reckoner including a wide range of information to facilitate everyday calculations prior to the widespread use of electrical calculators and devices. Published post 1945, the booklet also includes a chronology of World War 11 as well as a list of household antidotes in cases of poisoning.ready reckoner, calendars