If you have studied much 19th century American history, (which also probably means you have looked at thousands of photographs) you have probably noticed that people in photographs during this era did not usually smile, and that most women were not particularly attractive according to our modern standards.
I have heard various explanations as to why people didn't smile for photographs, and I have never been comfortable giving any one sole reason when asked about this phenomenon. Some say that people didn't smile because getting your picture made (or in contemporary language "your image struck") was a serious and expensive occasion...certainly no laughing matter. Others say that most people didn't have good dental health and didn't want to expose their bad teeth. Still others say that with slow lens speeds, it was difficult to hold a smile for the duration your photograph was being completed. I suppose any of those reasons, or a combination could be correct. I often wonder what must have been going through their heads the first time they had their picture taken..."Is this gonna hurt?," "What is he doing under that black curtain?," "Why is this taking so long?," or "Why do I have to sit so still?"
Being a male, I will keep my opinions of 19th century beauty to the female gender. I have never quite nailed down why most 19th century women are not very attractive; but I have several theories. I am sure that the hard work women had to perform had a toll on their appearance, and I can't imagine wood smoke and lye soap being very good for the complexion. I am sure that more than one women had singed brows from cooking over a fire. Women's hair fashions of the day didn't do much to enhance their looks either, unless possibly they had huge ears that could be hidden under their ubiquitous middle-part-pull-back-dos. Also, makeup was not nearly as accessible to women 150 years ago as it is today, (and lets face it, after seeing some pictures of modern celebrities without makeup...it can hide some serious flaws). But, I think we need to keep in mind that people in different times have different thoughts on attractiveness. They of course hadn't seen, for example a modern super model, so they have no modern basis of comparison. What is attractive today may not be attractive years from now...same as back then.
One timeless beauty from the past (at least in my humble opinion) is pictured above. She is Eliza Clindinst of New Market, Virginia. I think her symmetrical face and high cheek bones would still turn heads today. And while she is truly a natural beauty physically, her inner beauty became just as apparent after the Battle of New Market in May 1864, when she compassionately attended to the wounded and dying. To alter the famous Forrest Gump quote, "beauty is as beauty does."