It's All On The Line Together

A Dear Newbie has stumbled into a common misconception today and we should clear it up.
The flawed logic goes something like the following:
If Dear Newbie is a man, ...
...he knows about men's clothes...
...he is not a woman...
...he does not dress as a woman...
...he, therefore, would not know anything about clothing for persons of the female gender.

Whoa, whoa... Hold up there, Pard... that dog is maybe not gonna hunt.

Sure, Dear Newbie is a man and will research men's clothes...because he wears men's clothes. He'd also know some basics of women's and girls' clothes because he knows women (and probably girls too.)
Dear Newbie has a Mother and likely sisters too. They wear women's clothes. So, growing up, his drawers and Sister's drawers were beside each other on the clothesline and Mother's chemise was mended right along side Father's shirts. The conversations may have been whispered and not spoken of openly... but he may have heard about a "lady's time" too.
Dear Newbie, unless he is particularly naive, has likely assisted a woman out of her clothing at some point.  So, he has a basic idea of how women's clothing functions. He may fumble it and need her help, but it's not completely foreign.
If Dear Newbie is a common kind of man, he's likely married and he'd be passing familiar with his wife's clothing, though he doesn't speak of it and will call out anyone else who does.
 Perhaps Dear Newbie and his lady have been blessed with children. There's a chance some of those children will be girls. Girls who will wear female clothing. Who's clothing will go on the line next to Sonny's drawers and in the mending box next to his shirts.

The same can be applied to the Dear Newbie who is a woman. Men's clothing would not be as familiar as her own, but it would not be as foreign and scandalous as we often make it out to be.

So, we do a disservice to the people of the mid 19th century when a man cutely says, "I don't know 'nuthin' 'bout women's clothes."
They knew about clothing of the "opposite gender," they just didn't openly talk about it. Just like We don't openly talk about what goes on in the bedrooms of other people, and really prefer not to think about it too much (despite our love of celebrity scandals), Persons of the mid 19th century knew about clothing and just accepted it was there.
If we are to portray a person of the mid 19th century with a full range of knowledge, it's time we learn the basics of clothing the "opposite" gender.