IT WASN'T so long ago that women worked principally to earn what was known as "pin money"--enough to gild the cage, never enough to secure the key. While those times have gone the way of the gold standard and Richard Nixon, society persists in regarding the presence of women in the labor force as an act of childish whimsy. We continue to refer to our 50-year-old woman worker as a working girl or sales girl, girl at the front desk or girl Friday. And we continue to think of her earnings as "found money" with which to buy the marmalade for the hard-won bread of men.

This myth is repeatedly trashed by cold economic facts, only to be dutifully retrieved from the garbage heap by the media and put back into circulation. While newspapers report compassionately (and rightly so) on the job-retraining of male engineers laid off in the Route 128 recession or of returning Viet vets, they find no end of amusement in, say, the efforts of a young Worcester woman to train herself as an auto mechanic. More recently, there has been a growing recognition that many middle class women turn to work to relieve the psychic poverty of their lives. But America has yet to acknowledge the incontrovertible fact that the vast majority of women work neither for whim nor for pleasure. They work (as do the vast majority of men) because if they don't work, they won't eat.

A very fine study of working class women in America entitled Absent from the Majority has recently been published under the auspices of the American Jewish Committee. Its author, Nancy Seifer, brings to light a set of figures which ought to be general knowledge. Women now comprise 40 per cent of the labor force. One third of all working women are the only bread-winners in their households; another 8 per cent are the major ones. And as of 1870, seven-eighths of all women who held jobs were working simply to make ends meet.

The picture that emerges from Seifer's study is at once grim and quietly optimistic. In 1955, full-time women workers earned 64 per cent of the average full-time salary for men. Rather than narrowing, the gap is getting wider. In 1972, women earned only 59 per cent as much as men. And predictably enough, it is the blue-collar women workers, who can least afford to, who have shouldered the lion's share of that inequity. And as Seifer details, they have shouldered even more--the deadly tedium of the only kind of jobs they can get, and their own guilt and their husbands' resentment that they are working at all.

Given Seifer's statistics, why should there be any reason for optimism? Because increasing numbers of working women, having grown sick of how the script reads, are rewriting their lines. Enclaves of politically active women have sprung up in working-class communities across the country. The groups have formed around disparate issues, ranging from the racially-charged anti-busing movement to demands for adequate day-care facilities. But they all share one element in common--they have ruptured the time-honored pattern of female deference to authority and to circumstance.

THAT growing sense of power offers hope not only for the economic future of the working class, but also for the future of women in America. The women Seifer is talking about do not have the choices that, for instance, women at Radcliffe have. It is in no one's economic self-interest to offer these women a leg up; if they raise themselves, it will almost certainly be on their own steam. So it is ironic that these women, who must fight for every inch of ground on which they stand, are developing a strength which many of us, their more privileged sisters, have not begun to feel. We have been slipped into the backrooms of power by the male gatekeepers with a watchful eye on Title IX, E.R.A., affirmative action, and all those other impending legal nuisances. And, grateful for their charity, we have learned to walk softly, and to check our big sticks at the door. We tread with our fear kept quietly under wraps--unsure at every juncture if we can fight, and hoping to God we don't have to. For many of us there is a recurring sense of powerlessness--the same powerlessness we feel when we walk down a street at night, knowing that if we reach the other end in safety, it is because they choose not to rape us, not because we choose not to be raped.

America's working-class women have possibly the meanest street in the country to travel--and when they scream rape, almost no one will care. So they are learning a lesson which many more secure women have yet to learn--that we have not won ground until we are strong enough to hold that ground alone. And like the Vietnamese peasants fighting imperialism, they cannot give up the fight and go home--what they are fighting for is a home to go to. But working-class women are learning to fight well. In that reality there is hope for us all, particularly women who so far have underestimated their own potential strength.