Interesting take, Adrian, but this is another of JA's descriptions that make me realize that some things really don't change, even after two hundred years... Underlining words, and the liberal use of exclamation points are a time-honoured way for adolescent females to give vent to their feelings, especially in diaries and private letters! I remember in one of L.M. Montgomery's novels (I think it was the "Emily" series), the teenaged would-be author is admonished for underlining words too much and told to squelch the habit. Emily was partly based on L.M. Montgomery herself, who was born in 1874 - a century after JA, I admit, but I think it's still a useful clue!