These are referred to as boat inks. They're British and probably not as old as they look. I think (could be wrong) that these were still being manufactured this way into the 20th century. They were imported in large numbers to certain areas, I remember they were extremely common out in BC but I don't see many of them where I live now. Not sure how often they're found in the US, but I don't think they're a particularly common find down there because I rarely see them posted on here.
I'm not an English Ink collector, but it's always been my understanding that all those rough cracked lip British inks were generally known as penny inks. They were inexpensive and exported to about everywhere. I also believe they had a broad time range of usage and as someone else above said were used into the 20th century.
Whittle top or snap top inks. Correct that mostly import from the UK from 1890 through 1915's They range in values from $7 up to $35 depending on the shape and color. The one you have has several names Boat, Riverboat and Cabin. Here is a picture for you so see the many variations and colors they came in from my collection.
That one shaped like a pistol is fantastic, I've never seen one of those before! I love the blues as well, these types of inks were common where I used to live in BC but I never saw any that were close to that shade of blue.