waht is the context/significance of following part?

And now it only remains for me to offer my apologies for my blunt way of writing. I can only say in excuse for it that I am more accustomed to handle a rifle than a pen, and cannot make any pretence to the grand literary flights and flourishes which I see in novels—for I sometimes like to read a novel. I suppose they—the flights and flourishes—are desirable, and I regret not being able to supply them; but at the same time I cannot help thinking that simple things are always the most impressive ....