II. Its Experimental Tendency

It is probably only a coincidence that two medieval manu- impor- scripts close the Natural History in the midst of the seventy- t^^ce of sixth chapter of the last book with the words, "Experimenta tion and plurihus modis constant . . . Primum pondere/' ^ But al- gnce^'' though from the very nature of his work Pliny makes ex- tensive use of authorities, he not infrequently manifests a realization, as one dealing with the facts of nature should, of the importance of observation and experience as means of
quo exposuit et aperte declaravlt ana Florentiae adservantur, 1793-
plinius philosophus quid sit lapis 1795, II, 374-81.
philosophicus et ex qua materia 'De erroribus Plinii et aliorum
debet fieri et quomodo." in medicina, Ferrara, 1492.
* Fossi, Catalogus codicum ' Pliniana dcfensio, 1494.
saeculo XV itnpressorum qtd in * Escorial Q-I-4, and R-I-S, both
publico Bibliotheca Magliabechi- of the 14th century.
54 MAGIC AND EXPERIMENTAL SCIENCE chap!
reaching the truth. The claims of many Romans of high rank to have carried their arms as far as Mount Atlas, which Pliny declares has been repeatedly shown by experience to be most fallacious, leads him to the further reflection that nowhere is a lapse of one's credulity easier than where a dignified author supports a false statement.^ In other pas- sages he calls experience the best teacher in all things,^ and contrasts unfavorably garrulity of words and sitting in schools with going to solitudes and seeking herbs at their appropriate seasons. That upon our globe the land is en- tirely surrounded by water does not require, he says, inves- tigation by arguments, but is now known by experience.^ And if the salamander really extinguished fire, it would have been tried at Rome long ago.^ On the other hand, we find some assertions in the Natural History which Pliny might easily have tested himself and found false, such as his state- ment that an egg-shell cannot be broken by force or any weight unless it is tipped a little to one side.^ Sometimes he gives his personal experience,® but also mentions experience in many other connections. Use of The word employed most of the time by Pliny to denote
the word experience is experimentum? In many passages the word mentum. does not indicate anything like a purposive, prearranged, scientific experiment in our sense of that word, but simply the ordinary experience of daily life.® We are also told what experti,^ or men of experience, advise. In a number of passages, however, experimentum is used in a sense some-
*NH, V, I, 12. 41; VII, 56; VIII, 7; XIV, 8;
*XXVI, 6, "usu efficacissimo XVI, i ; XVI, 64; XVII, 2; XVII,
rerum omnium magistro" ; XVII, 35; XXII, i; XXII, 43; XXII,
2, 12, "quare experimentis optime 49! XXII, 51; XXV, 7; XXXIV,
creditur." 39 and 51. Experience is also the
3 jj 65 idea in the two following passages,
*XXIX 2'? although the word experimentum
*XXTx' TT could not smoothly be rendered as
4f;i;:[f'' • „ ,. „ "experience" in a literal transla-
-^ XXV 54, cora-mque nobis ; ^^^^. yn, 50, "Accedunt experi-
XXV, 106, 'nos earn Romanis ex- ^^^^^ ^^ exempla recentissimi
penmentis per usus digeremus. census . . ." ; XXVIII, 45, "Nee
' Sometimes another term, as uros aut bisontes habuerunt Graeci
usus in note 2 above, is employed. in experimentis."
"See II. 41, 1-2; II, 108; VII, "XVI, 24; XXII, 57; XXVI, 60.
n PLINY'S NATURAL HISTORY 55
what more closely approaching our "experiment." These are cases where something is being tested. For instance, a method of determining whether an tgg is fresh or rotten by putting it in water and watching if it floats or sinks is called an experimentiim} That horses would whinny at no other painting of a horse than that by Apelles is spoken of as illius cxperimentum artis, a test of, or testimony to, his art." The expression religionis experimento is applied to a religious test or ordeal by which the virginity of Claudia was vindi- cated,^ The word is also used of ways of telling if unguents are good^ and if wine is beginning to tum;^ and of various tests of the genuineness of drugs, gems, earths, and metals.®" It is also twice used of letting down a lighted lamp into a huge wine cask or into wells to discover if there is danger at the bottom from noxious vapors.''^ If the lamp was ex- tinguished, it was a sign of peril to human life. Pliny fur- ther suggests purposive experimentation in speaking of experimenta to discover water under ground ^ and in graft- ing trees. ^
Most of the tests and experiences thus far mentioned Experi- have been practical operations connected with husbandry and ^^^"clen-^
industry. But Pliny recounts one or two others which seem *'^.^ ^u"-
osity. to have been dictated solely by scientific curiosity. He classi- fies the following as experimenta: ^° the sinking of a well to prove by its complete illumination that the sun casts no shadow at noon of the summer solstice; the marking of a dolphin's tail in order to throw some light upon its length of life, should it ever be captured again, as it was three hundred years later — perhaps the experiment of longest duration on record; ^^ and the casting of a man into a pit of
* X, 75. 22 and 76 ; such phrases as sinceri
XXXV, 30. experimentiim and vcri experi-
VII, 35. mentum are used for "test o£
XIII, 3. genuineness."
'XIV. 25. 'XXIII, 31; XXXI, 28.
' XVII, 4 ; XX, 3 and 76 ; XXII, « XXXI, 27.
23; XXIX, 12; XXXIII, 19 and « XVII. 26.
43 and 44 and 57; XXXIV, 26 and '" II, 75.
48 : XXXVI, 38 and 55 ; XXXVII, " IX, 7.
56
MAGIC AND EXPERIMENTAL SCIENCE chap.
Medical experi- mentation.
Chance experience and divine revelation.
serpents at Rome to determine if he was really immune from their stings.^
Experimentum is employed by Pliny in a medical sense which becomes very common in the middle ages. He calls some remedies for toothache and inflamed eyes certa experi- menta — sure experiences.^ Later experimentum came to be applied to almost any recipe or remedy. Pliny, indeed, speaks of the doctors as learning at our risk and getting experience through our deaths.^ In another passage he states more favorably that "there is no end to experimenting with everything so that even poisons are forced to cure us." * He also briefly mentions the medical sect of Empirics, of whom we shall hear more from Galen. He says that they so name themselves from experiences ^ and originated at Agrigentum in Sicily under Acron and Empedocles.
Pliny is puzzled how some things which he finds stated in "authors famous for wisdom" were ever learned by ex- perience, for example, that the star-fish has such fiery fervor that it burns everything in the sea which it touches, and di- gests its food instantly.® That adamant can be broken only by goat's blood he thinks must have been divinely revealed, for it would hardly have been discovered by chance, and he cannot imagine that anyone would ever have thought of testing a substance of immense value in a fluid of one of the foulest of animals. ''^ In several other passages he suggests chance, accident, dreams,® or divine revelation as the ways in which the medicinal virtues of certain simples were dis- covered. Recently, for example, it was discovered that the root of the wild rose is a remedy for hydrophobia by the mother of a soldier in the praetorian guard, who was warned * XXVIII, 6.
'XXVIII, 14.
•XXIX, 8. "Discunt periculis nostris et experimenta per mortes agunt." Bostock and Riley trans- late the last clause, "And they ex- perimentalize by putting us to death." Another possible transla- tion is, "And their experiments cost lives."
*XXV, 17. ". . . adeo nullo omnia experiendi fine ut cogeren- tur etiam venena prodesse."
'XXIX, 4 "... ab experimen- tis se cognominans empiricen."
• IX, 86. 'XXXVII, 15.
* According to Galen, as we shall hear later, the Empirics relied a good deal upon chance experience and dreams.
II PLINY'S NATURAL HISTORY 57
in a dream to send her son this root, which cured him and many others who have tried it since. ^ And a soldier in Pompey's time accidentally discovered a cure for elephan- tiasis when he hid his face for shame in some wild mint leaves.^ Another herb was accidentally found to be a cure for disorders of the spleen when the entrails of a sacrificial victim happened to be thrown on it and it entirely consumed the milt.^ The healing properties of vinegar for the sting of the asp were discovered by chance in this wise. A man who was stung by an asp while carrying a leather bottle of vinegar noticed that he felt the sting only when he set the bottle down.* He therefore decided to try the effects of a drink of the liquid and was thereby fully cured.^ Other remedies are learned through the experience of rustics and illiterate persons, and yet others may be discovered by ob- serving animals who cure their ills by them,*' Pliny's opinion is that the animals have hit upon them by chance.
Pliny represents a number of marvelous and to us in- Marvels credible things as proved by experience. Divination from gxperi- thunder, for instance, is supported by innumerable experi- ence. ences, public and private. In two passages out of the three mentioning experti which I cited above, those experienced persons recommended a decidedly magical sort of procedure.'^ In another passage "the experience of many" supports "a strange observance" in plucking a bud.^ A fourth bit of magical procedure is called "marvelous but easily tested." * Thus the transition is an easy one from signs of experimen- tal science in the Natural History to our next topic, Pliny's account of magic.
^ XXV, 6. mouth, it will prevent one from
' XX, 52. feeling the heat in the baths.
" XXV, 20. ' XXV, 6 and 21 and 50 ; XXVII,
* XXIII, 27. 2.
"Among other virtues of vine- 'XVI, 24; XXVI, 60.
gar, besides its supposed property * XXIII, 59.
of breaking rocks, Pliny mentions * XXVIII, 7. that if one holds some in the
S8 MAGIC AND EXPERIMENTAL SCIENCE chap.