The mistake, shown in all the old maps of Australia, had originated in a curious optical illusion.
In length by any mirrors which can be practically constructed would be like attempting optical experiments with mirrors one-hundred-thousandth of an inch in diameter.
Malt, tinware, flour and grist-mill products, boilers, stoves and ranges, optical supplies, wall-paper, cereals, canned goods, cutlery, tin cans and wagons are manufactured, and there are also extensive nurseries.
His optical investigations are perhaps the subject in which he most contributed to the progress of science; and the lucidity of exposition which marks his Dioptrics stands conspicuous even amid the generally luminous style of his works.
In their optical characters the micas exhibit considerable variations.