JOHN COOPER & SONS (MELBOURNE).
The Genderometer, or Sex Indicator.
Melbourne : John Cooper & Sons, [between 1910 and 1920]. Cardboard box with textured paper covering, 40 x 40 x 20 mm, underside with printed label of ‘John Cooper & Sons, “Reliable Ironmongers”, 299 Elizabeth St. Melb.’; contains a small metallic object with a length of fine wire attached, accompanied by a folding printed and illustrated sheet of instructions, 125 x 115 mm, titled ‘Directions for using The Genderometer, or Sex Indicator’, recto and verso with Cooper & Sons wet stamp (a couple of tears to the edges of the folds, without loss of text); complete.
A fascinating “folk science” curio made and marketed in Melbourne in the World War I period. Even today, in-ovo sexing using spectroscopy is not 100% accurate!
‘A small metal bullet shape which is attached to a piece of string and is used to determined the sex of the chicken. The cord is held and the metal part is about less than a quarter of an inch above the egg. Within a half a minute the tester usually begins to move. If the egg is a rooster the bullet shape metal piece will swing backwards and forwards, if the egg is a hen it will move in circles. This genderometer or sex indicator is still in use and is very accurate.’ (Woodsdale Museum, Tasmania)