All those pics stem from a series of parental guidebooks that was issued in Sweden during the 60´s- 80´s.
They all show how european rectal thermometers should be used on different children depending on their age.
I don´t know if the pics are just demonstrational or real live shots. To me it seems as none of the thermometers are properly inserted. They just appear to be held close or put between the buttocks.