The Martyrs of Science, or, The lives of Galileo, Tycho Brahe, and Kepler

t the orbit of Mars is an Ellipse, with the Sun in one focus-And extends this discovery to all the other Planets-He establishes the two first laws of Physical Astronomy-His Family Distresses-Death of

e of Style-He refuses the Ma

ear. Owing to this cause he was constantly involved in pecuniary difficulties, and, as he himself described his situation, he was perpetually begging his bread from the Emperor at Prague. His increasing family rendered the want of money still more distressing, and he was driven to

A Supplement to Vitellio, in which the optical part of astronomy is treated, but chiefly on the artificial observation and estimation of diameters, and of the eclipses of the Sun and Moon." Astronomers had long been perplexed with the refraction of the atmosphere, and so little was known of the general subject, as well as of this branch of it, that Tycho believed the refraction of the atmosphere to cease at 45° of altitude. Even at the beginning of the second century, Claudius Ptolemy of Alexandria had unravelled its principal mysteries,

f the light, he was nearer the goal, in his first speculation, than in any of the rest; and he seems to have failed in consequence of his not separating the question as it related to density from the question as it related to incidence. "I did not leave untried," says he, "whether, by assuming a horizontal refraction according

object. He ascribed an erect vision to an operation of the mind, by which it traces the rays back to the pupil, where they cross one another, and thus refers the lower parts of the image to the higher parts of the object. He also explained the cause of long-sighted and short-sighted vision, and shewed how convex and concave lenses enabled those who possessed these peculiarities of vision to see distinctly, by accurately converging the pencils of rays to a focus on the retina. Kepler likewise

n, contains the method of calculating ecli

sparent bodies with convex and concave surfaces, and of determining the foci of lenses, and of the relative positions of the images which they form, and the objects from which the rays proceed. He was thus led to explain the rationale of the telescope, and to invent the astronomical telescope, which consists of two convex lenses, by which objects are seen inverted. Kepler also discovered the important fact, that spherical surfaces were not capabl

ermine would have adorned the history of another century. Having tried in vain to represent the motion of Mars by an uniform motion in a circular orbit, and by the cycles and epicycles with which Copernicus had endeavoured to explain the planetary inequalities, Kepler was led, after many fruitless speculations,[46] to suppose the orbit of the planet to be oval; and, from his knowledge of the conic sections, he afterwards determined it to be an ellipse, with the sun placed in one of its foci. He then ascertained the dimensions of the orbit; and, by a comparison of the times employed by the planet to complete a whole revolution or any part of one, he discovered that the time in which Mars describes any arches of

upply the wants of science. While Kepler was thus involved in the miseries of poverty, misfortunes of every kind filled up the cup of his adversity. His wife, who had long been the victim of low spirits, was seized, towards the end of 1610, with fever, epilepsy, and phrenitis, and before she had completely recovered, all his three children

Linz, which was now vacant; but, upon his return in June, he found his wife in a decline, brought on by grie

the arrears of his salary would be paid from Saxony; but these hopes were fallacious, and it was n

own time was so completely occupied by his new professorial duties, as well as by his private studies, that he found it necessary to seek another parent for his children. For this purpose, he gave a commission to his friends to look out for him a suitable wife

r too proud of her birth and quarterings, a fourth had learned nothing but shewy accomplishments, "not at all suitable to the sort of life she would have to lead with me," another grew impatient, and married a more decided admirer, whilst he was hesitating. "The mischief," says he, "in all these attachments was, that whilst I was delaying, comparing and balancing conflicting reasons, every day saw me inflamed with a new passion." By the time he reached the 8th, he found his match in this respect. "Fortune at length has avenged herself on my doubtful inclinations. At first she was quite complying, and her friends also; presently, whether she did or did not consent, not only I, but she herself did not know. After the lapse of a few days came a renewed promise, which, however, had to be confirmed a third time; and four days after that, she again repeated her confirmation, and begged to be excused from it. Upon this I gave her up, and this time all my counsellors were of one opinion." This was the longest courtship in the list, having lasted three whole months; and, quite disheartened by its bad success, Kepler's next attempt was of a more timid complexion. His advances to No. 9 were made by confiding to her the whole story

wry, by favour of the Lady of Stahrenberg, the strictness of whose household is famous throughout the province. Her person and manners are suitable to mine-no pride, no extravagance. She can bear to work; she has a tolerable knowledge how to manage a family; middle-aged, and of a d

e found it necessary to stock his cellar with a few casks of wine. When the wine-merchant came to measure the casks, Kepler objected to his method, as he made no allowance for the different sizes of the bu

s services, yet his pension was allowed to fall in arrear, and, in order to support his family, he was obliged to publish an Almanac, suited to the taste of the age. "In order," says he, "to defray the expense of the Ephemeris for two

maintain, on account of some opinions which he had expressed respecting transubstantiation, yet he refused, in 1617, to accept of an invitation to fill the mathematical chair at Bologna. The prospect of his fortune being bett