You could get a considerable sum for the exclusive right to take your likeness; and, if you chose to explain it, you might fix your own price on the novel motive power you have introduced.

But there is another point in regard to the contract which you have overlooked, but which I was bound to bear in mind.

What you have promised is, I believe, what Eveena would have obtained from any suitor she was likely to accept.

But since you left the matter entirely to my discretion, I am bound to make it impossible that you should be a loser; and this document (and he handed me a small slip very much like that which contained the marriage covenant) imposes on my estate the payment of an income for Eveena's life equal to that you have promised her." With much reluctance I found myself obliged to accept a dowry which, however natural and proper on Earth, was, I felt, unusual in Mars.

I may say that such charges do not interfere with the free sale of land.
They are registered in the proper office, and the State trustee collects them from the owner for the time being as quit-rents are collected in Great Britain or land revenue in India.