If You Had A Time Machine?

I'm assuming the machine is multiple-use (as in, I can return back to the present, go to the past again, etc). I am also assuming it can travel in space as well as time (as in, I can set my arrival as "Philadelphia 1837" even if my location in the present is nowhere near Philadelphia).

In this case... well, first thing I do, as a test, is take my dateless Matron Head cent, go to, well, Philadelphia 1837, and ask somebody to give me two half-cents for it (if they only give one, fine, it was just about worthless anyway).
Then I take my Shield nickel (don't remember the exact date, but it's in the 1860s), go to the 1870s (hadn't decided what year specifically) and exchange it into whatever smaller coinage they have... the earlier the better, but anything works really.
Then - that's the good part - I buy a bunch of common Maria Theresa thalers, and go to the mint (mainly Philadelphia) at various dates between 1792 and 1857 (or whenever they stopped accepting foreign money - could be 1853) to exchange them for various US coins. There's really no way they could tell that the coins I'm giving them aren't authentic 18th-century money, and, well, they are real silver, so I'm not really scamming anyone either.

On second thought, a big problem would be contemporary clothes - I've no idea where to get anything applicable for the 1830s (or any other time period before the last several decades), and anything modern is going stick out. That would probably make this entire plan very unlikely (but of course the initial scenario of me somehow getting a time machine doesn't sound particularly likely either).

So many people have brought this up here and lots of places. Ever watch the Big Bang Theory TV show? They mention this time travel a lot.
One thing though is if anyone did go back and say grabbed all the 1916D Mercury dimes they could find, yes it would change our present documentation of them. There would possibly be a record of so many vanishing so it would be assumed they are hoarded and the value would drop on all of them. Maybe.
There is no problem with the money we could take back in time. Just go to any coin show, purchase all the low valued Dimes of say 1917. Now simply go to 1917 and trade anyone you find with a 16D for a 17. Here is the possible problem with all that. When you take all those 1917 Dimes back to 1917, they may be in someone's pocket back then. They would suddenly pop out to your hands and you would be a criminal in 1917 although you never existed back then.
Now you go to prison for 20 years although you never existed. If you had been married in 2014, that would not have taken place. Now when you come back a lady with your kids is looking for you with a gun for abandoning her here in the present. She shoots you, so now all your coins are taken to a bank and simply deposited by her.
And you want to go back in time?

If people are going back to the mid or early 1800s, they can just bring a few lbs of aluminum with them. That'll go even further than gold, and it can be had cheaply now.

The worst part of going back in time and acquiring any coins is how much things would be effected by that. IF you even took one 1916D Dime back from the past, imagine all the places, people, things it could have come in contact with. None of those would have happened and possibly everything you ever knew would no longer be the same when you got back. Possibly even coin collecting would have been outlawed. Your one 1916D Mercury dime would now be something that could have you put to death in this new present.
OR nothing would have changed since it already happened so now is the way things could have been anyway.

Has anyone ever thought that the hordes of 1652 schillings, or BU large cents, cans and jars of gold coins , or casks of early silver coins pulled from circulation were because of the hand of a time traveller who accumulated all of these coins, hid them in a secret hiding spot so that when they come back in 200 or so years, they would "discover" the horde of coins and put them on the market for a hefty profit. However, the efforts were thwarted when people discover the hordes before the time traveller's present day. Thus we have hordes and high grade coins for everyone!

What about the true and recorded story from the 1880's about a farmer who saw an aircraft hovering above his field, take a cow, and leave. The farmer described the aircraft as hiving rails like a sleigh (like a helicopter). Also take into account that this was a farmer that was probably not too keen in science, and the story was recorded more than 20 YEARS BEFORE SUSTAINED AIR TRAVEL WAS POSSIBLE.