Note that the pen has no nib. By the 1830's, quill pens, which sucked up ink into their hollow via capillary action and required that the feather be often sliced at its point to maintain a sharp nib, had been replaced by dip pens with steel nibs (the pen itself) inserted into pen-holders, as here. Steel nibs were sturdier, kept their sharpness, lasted longer, and had the added advantage of being a much neater implement, not spilling ink all over paper and fingers.
Those were the days. If you're a pen and ink aficionado, as I am, you'll salivate over Kierkegaard's gorgeous pen.