THE VAL DI CHIANA. 533 
south-eastwards until it strikes into the valley of the Paglia, a 
tributary of the Tiber, and thus connects the basin of the latter 
river with that of the Arno. In the Middle Ages, and down 
to the eighteenth century, the Val di Chiana was often over- 
flowed and devastated by the torrents which poured down from 
the highlands, transporting great quantities of slime with their 
currents, stagnating upon its surface, and gradually converting 
it into a marshy and unhealthy district, which was at last very 
greatly reduced in population and productiveness. It had, in 
fact, become so desolate that even the swallow had deserted 
it.* 
The bed of the Arno near Arezzo and that of the Paglia at 
the southern extremity of the Val di Chiana did not differ 
much in level. The general inclination of the valley was there- 
* This curious fact is thus stated in the preface to Fossombroni (Memorie 
sopra la Val di Chiana, edition of 1835, p. xiii.), from which also I borrow 
most of the data hereafter given with respect to that valley: ‘‘ It is perhaps 
not universally known, that the swallows, which come from the north [south] 
to spend the summer in our climate, do not frequent marshy districts with a 
malarious atmosphere. A proof of the restoration of salubrity in the Val di 
Chiana is furnished by these aérial visitors, which had never before been seen 
in those low grounds, but which have appeared within a few years at Forano 
and other points similarly situated.” 
Is the air of swamps destructive to the swallows, or is their absence in such 
localities merely due to the want of human habitations, near which this half- 
domestic bird loves to breed, perhaps because the house-fly and other insects 
which follow man are found only in the vicinity of his dwellings ? 
In almost all European countries the swallow is protected, by popular 
opinion or superstition, from the persecution to which almost all other birds 
are subject. It is possible that this respect for the swallow is founded upon 
ancient observation of the fact just stated on the authority of Fossombroni. 
Ignorance mistakes the effect for the cause, and the absence of this bird may 
have been supposed to be the occasion, not the consequence, of the unhealthi- 
ness of particular localities. This opinion once adopted, the swallow would 
become a sacred bird, and in process of time fables and legends would be in- 
vented to give additional sanction to the prejudices which protected it. The 
Romans considered the swallow as consecrated to the Penates, or household 
gods, and according to Peretti (Le Serate del Villaggio, p. 168) the Lombard 
peasantry think it a sin to kill them, because they are le gallinelle del Signore, 
the chickens of the Lord. 
