Tory Bilski could have called her well-written and witty memoir of riding horses in northern Iceland “Wild Horses of the Midnight Sun,” but in naming it “Wild Horses of the Summer Sun,” shows her writing creds: the alliteration effectively plays on the popular image many people associate with this starkly beautiful land of lupine fields and black volcanic sand banks – not to mention Johnny Mercer’s lyrics in that old jazz standard, “Midnight Sun.” Like Mercer, Bilski evokes a nostalgic warmth for what is gone but indelibly remembered because it was so affecting. In “Wild Horses of the Summer Sun” the love is for Icelandic horses and the country, not far from the Arctic Circle. An unusual destination when Bilski started going years ago, having heard about the horses from a woman who owned a horse farm in the Berkshires. The marvel of this moving, funny, episodic narrative is that Bilski turns living on a horse farm in Iceland with other women for a week every June into a universal story