Costard, in his History of Astronomy, makes some critical remarks on the name of this greater light. He says, The sun is, by the Greeks, called <<Hêlios>>: which is nothing more than the Hebrew word **'l** _El_, modelled after the Greek manner of pronunciation, and signifies _Lord_; the first idolatrous worship being paid to this planet. In the Hebrew language it is called **shmsh** _Shemesh_, and in the Chaldee **shmsh'** _Shimsha_, from **shmsh** _Shamesh_, to _minister_, on account of its administering light and heat to this world. From this property of communicating heat, it is also called **hmh** _Hammah_. By the Phoenician idolaters it seems to have been called **b`l** _Baal_, or **b`l shmym** _Baal-Shamim_, the _Lord of Heaven_. And on account of the supposed swiftness of its diurnal motion from east to west, it had a chariot dedicated to it at Sidon, an ancient town of Phoenicia. Such a chariot is still seen on the coins of that place. This superstition was likewise imitated by the idolatrous Jews: for we read of _the horses which the kings of_ Judah _had given_, or dedicated, _to the sun_. By the Chaldeans it seems to have been called **bl** _Bel_, and by the Assyrians **pl** _Pul_; and, with the addition, sometimes of **'b** _ab_, or **'p** _ap_, i.e. _father_, **'p-pl** _Ap-Pul_, or _Father-Lord_; from whence the Greeks formed their <<Apollôn>>, another name given by them to the sun. The name of this luminary, among the Romans, was _sol_; given more probably, on account of his scorching heat in the summer, or from his determining the length of the year by his course, than because he appeared _solus, alone_, according to the derivation given by Macrobius.
The _nature_ of the sun is a subject which has not only excited the most diligent inquiry among men of scientific knowledge, but the opinions concerning it have passed through a variety of vicissitudes. The sun being evidently the source of light and heat, was by the ancients considered to be a globe of fire. But Dr. Herschell's discoveries, by means of his immensely large telescopes, tend to prove, that what we call the _sun_ is only the _atmosphere_ of that luminary: "that this atmosphere consists of various _elastic fluids_, which are more or less transparent; that as the clouds surrounding our earth are probably decompositions of some of the elastic fluids belonging to the atmosphere itself, so we may suppose that in the vast atmosphere of the sun similar decompositions may take place, but with this difference, that the decompositions of the elastic fluids of the sun are of a _phosphoric_ nature, and are attended by lucid appearances, by giving out light." The body of the sun this celebrated astronomer considers as hidden generally from us, by means of this luminous atmosphere; that what are called _maculæ_, or _spots_ on the sun, are real openings in this atmosphere, through which the _opaque body_ of the sun becomes visible; that this atmosphere itself is not _fiery_ nor _hot_, but is the instrument which God designed to act on the caloric or latent heat; and that heat is only produced by the solar light acting on and combining with the caloric or matter of fire contained in the air, and other substances which are heated by it.