Four Early Japanese CDV

Subjects:

1. Panoramic view of a harbor
2. View of a bridge leading into an enclosed area (castle?)
3. View of a city looking out from a balcony
4. View of a wooden building (perhaps a castle behind that) with man in foreground

All three cards have writing on the back. The 4th item has what I believe to be "Nagasaki" written in Japanese on the back.

The "story" related with the cards (can not be verified) is that an American sailor brought them back after a voyage to Japan in 1868. The first image with the ships in harbor is said to be Nagaski harbor.

Type of Prints. I am unsure of the type of photographic prints these are.