Differences in curve and finish are a natural result of these two pen positions.
As Mr. Dwiggins explains: "In writing lower-case 'a,' for example, the stroke begins at the little bulb at the upper left-hand corner, passes over the arch at the top, descends to form the straight stem, and finishes with an upward flick; a second motion forms the loop. As the line moves, it swells and thins in accordance with the shape of the pen and the direction of the movement.
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"In the Caslon letter (i), the swelling at the top begins at the bulb or dot; the arch expands throughout its whole curve; the loop has a decided tilt, as has the finishing stroke.
"In the Scotch letter (j), the arch is a thin line; the expansion does not begin until the downward stroke of the stem; the swelling of the loop is at right angles to the line of writing, and the letter ends with a perpendicular flick.
"In the 'b,' one notices the difference in the loops and in the serifs at the tops of the letters.
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