[16] “All the Year Round,” by Dickens.
[17] Dr. Lardner’s Museum of Science, p. 115.
“The light of the Moon though concentrated by the most powerful burning glass, is incapable of raising the temperature of the most delicate thermometer. M. De La Hire collected the rays of the full Moon when on the meridian, by means of a burning glass thirty-five inches in diameter, and made them fall on the bulb of a delicate air-thermometer. No effect was produced, though the lunar rays by this glass were concentrated 300 times.” “Professor Forbes concentrated the Moon’s light by a lens thirty inches in diameter, its focal distance being about forty-one inches, and having a power of concentration exceeding 6,000 times. The image of the Moon which was only eighteen hours past full, and less than two hours from the meridian, was brilliantly thrown by this lens on the extremity of a commodious thermo-pile. Although the observations were made in the most unexceptional manner, and (supposing that half the rays were reflected, dispersed, and absorbed) though the light of the Moon was concentrated 3000 times, not the slightest thermo-effect was produced![18] In the “Lancet” (medical journal) for March 14th, 1856, particulars are given of several experiments, which proved that the Moon’s rays when concentrated actually reduced the temperature upon a thermometer more than 8 degrees!
[18] Dr. Noad’s Lectures on Chemistry, p. 334.
“The cold chaste Moon, the Queen
Of Heaven’s bright Isles;
Who makes all beautiful
On which she smiles:
That wandering shrine of soft
Yet icy flame,