Outmoded medical procedure, once widely used by general practitioners and midwives as a treatment for hysteria, and often other maladies as well.
The basic idea is to get a couple of fingers into the vagina, rub the cervix and/or top surface, twiddle around with the thumb, and continue until "hysterical paroxyism" or spasmodic contractions of the uterus, occur.
Get your mind out of the gutter, this is therapy!
Sorry. It actually is what it sounds like, a therapeutic handjob. As a matter of fact, the electric vibrator was intended as a labor-saving device for busy doctors, weary of palpating quim all day on Victorian widows and spinsters suffering from such symptoms as nervousness, weariness, paralysis, odd aches and pains, fluid retention, and "a tendency to cause trouble". Apparently, medical science, dominated by male attitudes and the notion that sex! = procreation just didn't realize until about a hundred or so years ago that even though orgasm is less dramatic in women, it's much the same thing. Since hysteria was by and large nonfatal but chronic, and treatment had to continue (at least) weekly for life, it was a major cash cow for many physicians. Surprisingly, despite this, and the undoubted gratitude of their patients, most doctors considered this task onerous and boring.
What's really shocking, however, is how widespread this 'therapy' was and for how long it was practiced. Hippocrates himself is said to have written on the "wandering womb", which, hungry, slowly strangled the woman once it reached her chest, who is said to have gotten the idea from some older Egyptian papyri which diagnosed and treated the malady in much the same way. (Apparently, this didn't seem to be covered as 'seduction' under the Hippocratic Oath.) Medieval textbooks even prescribed it to nuns, and recommended the use of scented and/or spicy oils to hasten the procedure (yum!), but relegated the process to midwives since the precise technique proved 'hard to master for men'; it was recommended to Marie Antoinette as a cure for her (early) infertility. In the 18th-19th centuries, spas such as Bath promoted 'pelvic hydrotherapy' (similar to techniques promoted in the 1970s book "The Sensuous Woman") as a treatment, even Kellogg's Sanitarium, which strongly promoted celibacy as an ideal, used this treatment extensively on female patients.
However, by the 1920s, the jig was up: vibrators were considered quack devices (though available through ads in sleazy magazines and health food stores), and the women of America had to wait until the 60s to get ... a few good vibrations.