Shelley Sonnet on Ballooning

Bright ball of flame that thro the gloom of even Silently takes thine ethereal way And with surpassing glory dimmst each ray Twinkling amid the dark blue depth of Heaven; Unlike the Fire thou bearest, soon shalt thou Fade like a meteor in surrounding gloom, Whilst that, unquenchable, is doomed to glow A watch-light by the patriot’s lonely tomb, A ray of courage to the opprest and poor…

 Focusing Light Increases Heat Where Focused

The sun's rays proceed from the sun along straight lines and are reflected from every polished object at equal angles, i.e. the reflected ray subtends, together with the line tangential to the polished object which is in the plane of the reflected ray, two equal angles. Hence it follows that the ray reflected from the spherical surface, together with the circumference of the circle which is in the plane of the ray, subtends two equal angles. From this it also follows that the reflected ray, t...