No. 379 of the Spectator relates an anecdote of a person who had opened
the sepulchre of the famous Rosicrucius. He discovered a lamp burning,
which a statue of clock-work struck into pieces. Hence, the disciples of
this visionary said that he made use of this method to show "that he had
re-invented the ever-burning lamps of the ancients."
Many writers have made mention of these wonderful lamps.
It has happened frequently that inquisitive men examining with a
flambeau ancient sepulchres which had been just opened, the fat and
gross vapours kindled as the flambeau approached them, to the great
astonishment of the spectators, who frequently cried out "_a miracle!_"
This sudden inflammation, although very natural, has given room to
believe that these flames proceeded from _perpetual lamps_, which some
have thought were placed in the tombs of the ancients, and which, they
said, were extinguished at the moment that these tombs opened, and were
penetrated by the exterior air.
The accounts of the perpetual lamps which ancient writers give have
occasioned several ingenious men to search after their composition.
Licetus, who possessed more erudition than love of truth, has given two
receipts for making this eternal fire by a preparation of certain
minerals. More credible writers maintain that it is possible to make
lamps perpetually burning, and an oil at once inflammable and
inconsumable; but Boyle, assisted by several experiments made on the
air-pump, found that these lights, which have been viewed in opening
tombs, proceeded from the collision of fresh air. This reasonable
observation conciliates all, and does not compel us to deny the
accounts.
The story of the lamp of Rosicrucius, even if it ever had the slightest
foundation, only owes its origin to the spirit of party, which at the
time would have persuaded the world that Rosicrucius had at least
discovered something.
It was reserved for modern discoveries in chemistry to prove that air
was not only necessary for a medium to the existence of the flame, which
indeed the air-pump had already shown; but also as a constituent part of
the inflammation, and without which a body, otherwise very inflammable
in all its parts, cannot, however, burn but in its superficies, which
alone is in contact with the ambient air.