public void PositionHydrogenCount()
        {
            var hydrogenCount = new TextOutline("2", font, emSize);
            var positioned    = atomGenerator.PositionSubscript(hydrogen, hydrogenCount);

            var hydrogenBounds      = hydrogen.GetBounds();
            var hydrogenCountBounds = positioned.GetBounds();

            Assert.IsTrue(hydrogenCountBounds.Left > hydrogenBounds.Left);
            Assert.AreEqual(hydrogenBounds.Bottom, hydrogenCountBounds.CenterY(), 0.01);
        }