Because I’m an aspiring writer and find this interesting, I’m covering this first. In most cases all authors write to their audiences from the context of their personal experience. In verse six, Nephi mentions a river of water. Sounds simple enough, but why not just say, “a river?” Why go to the trouble to explain it was a river in which water is flowing? Answer: raised in a desert with many dry river beds, wadis, a river that actually had flowing water was extraordinary. So, Nephi made mention of that distinction. From his experience, it was natural to say so.
Here’s the kicker. Raised in New England, rivers and creeks had water in them all year round. A dry river would have been extraordinary. If Joseph had been making it up, he would likely have just said, “a river.” Slim evidence you say?
Now, consider this...for years, decades even, critics used this as evidence against the Book of Mormon since they say there’s no geological evidence to corroborate his claim. Enter Google Earth. About 75 miles south of Jerusalem, there’s a fissure in the desert leading to the Red Sea, an impressive one which contains a dry river bed and palm trees. Geologists say there is evidence that 2500 years ago, the river probably flowed continuously, fed by runoff from distant mountains. There's even a shrine in there. I've seen pictures of the place, it's an impressive "valley". No maps in Joseph's day showed this. So, did he just guess correctly? If the critics are correct, he's made quite a few good ones. Just sayin'.
Here’s my abbreviated bit about Laman and Lemuel. Getting shaken by the spirit when Nephi spoke to them in Bountiful isn’t the first time this happened to these two. In verse 14 we read that Lehi speaking to them did it too. Some people just never learn.