Sun-bath

Baths of various kinds are indulged in, but the chief bath relied on is the "sun-bath."

Source: wiktionary

Personally, I am very glad that I remained behind when the troops and so many of our citizens left, for though the living is rough and the climate is infernal, still by dint of the three voyages which I have made for amber to the Baltic, and the excellent prices which I obtained for it here, I shall soon be in a position to retire, and to spend my old age under my own fig tree, or even perhaps to buy a small villa at Baiae or Posuoli, where I could get a good sun-bath after the continued fogs of this accursed island.

Source: wiktionary

The nights' rests were therefore seldom long, but the mid-day rests, during which a glorious warm sun-bath was enjoyed, were taken on a proportionately generous scale, affording opportunities for taking observations both for altitude and longitude.

Source: wiktionary