A. J. Pleasonton

1808 – 1894

• The influence of the blue ray of the sunlight and of the blue colour of the sky
• On the influence of the blue color of the sky in developing animal and vegetable life
• The influence of the blue ray of the sunlight and of the blue color of the sky
• The influence of the blue ray of the sunlight and of the blue colour of the sky
• On the influence of the blue color of the sky in developing animal and vegetable life, as illustrated in experiments between the years 1861 and 1871 at Philadelphia