I first discovered Giorgione and the Tempest in Edward Hutton's, Venice and Venetia, originally published in 1911.* The book was one of many that Hutton came to write on Italy, its regions, cities, culture and history. I had first encountered Hutton in his enchanting book on Lombardy and soon began to collect as many of his books as I could. In preparation for a trip to Venice in 2005 I opened Venice and Venetia and found this passage in his account of the Palazzo Giovanelli, at that time the home of the Tempest.
In 1560 Jacopo Sansovino restored the Palace, which, however, did not remain in the hands of the Urbino Dukes but passed to the Dona family by purchase; they in the seventeenth century passed it on to the Giovanelli, who still hold it and its treasures, undoubtedly the greatest of these is the picture by Giorgione, which has passed under various names—the family of Giorgione, or simply the Gipsy and the Soldier—which in itself sums up all that we mean by the Giorgionesque in painting. There we see, in a delicious landscape of green and shady valley, of stream and ruin and towered country town, a woman nude but for a cape about her shoulders giving her breast to her child in the shadow of the trees by a quiet stream. On the other side of this jeweled brook a young man like a soldier—or is it a shepherd?—stands resting on a great lance or crook and seems to converse with her. Close by are ruins of some classical building overgrown by moss and lichen, and half hidden in the trees, and not far off up the stream in the sunset we see the towers and walls and roofs and domes of a little town with its bridge across the stream leading to the great old fortified gate of the place. But what chiefly attracts us in the work is something dreamlike too, though wholly of this our world, an air of music which seems to come to us from the noise of the brook or the summer wind in the trees, or the evening bells that from far off we seem to hear ring Ave Maria. One of the golden moments of life has been caught here for ever and perfectly expressed. Heaven, it seems, the kingdom of Heaven, is really to be found in our midst, and Giorgione has contrived a miracle the direct opposite of that of Angelico; for he found all the flowers of Tuscany and the byways of the world in far-off Paradise, but Giorgione has found Paradise itself here in our world. And we must remember that such a work as this was the true invention of Giorgione. 
Hutton understood Giorgione's significance.
For with Giorgione (1478-1510), the pupil of Giovanni Bellini…we have a new creation in Art; he is the first painter of the true “easel picture,” the picture which is neither painted for church not to adorn a great public hall, but to hang on the wall of a room in a private house for the delight of the owner. For Giorgione the individual exists, and it is for him, for the most part, he works, and thus stands on the threshold of the modern world….In these short thirty-two years, however, he found time to re-create Venetian painting, to return it to its origins, and to make the career of his great fellow-pupil, Titian, whom he may be said to have formed, possible.
For the truth is that Giorgione, Titian, and Tintoretto are each an absolutely new impulse in painting. Fundamentally they owe nothing, accidentally even very little, to their predecessors; and if, as we have said, Titian and Tintoretto were able to find full expression because of the work of Giorgione, it is only in the way that Shakespeare and Milton may be said to owe something…to Spencer;…the work of Giorgione, Titian, and Tintoretto are absolutely new things in the world, the result of a new impulse and a new vision, individual and personal to the last degree, owing little to any school and making little of tradition. 
Hutton was a student of Roman and Italian history and art but he also made it a point to see everything he wrote about. He used every means of conveyance to get about and often covered the ground on foot. His descriptions of his walking tours in both town and country are charming and informative. Here is his description of Giorgione's home town of Castelfranco, and its most prized possession.
This little city…is the happy possessor of what will ever remain, I suppose, the work that is most certainly his very own—I mean the altarpiece of the Madonna enthroned with her little Son between S. Francis and S. Liberale. This glorious picture…is one of the very few Venetian pictures…which possess that serenity and peace, something in truth spellbound, that is necessary to and helps to make what I may call a religious picture. For something must be added to beauty, something must be added to art, to achieve that end which Perugino seems to have reached so easily, and which almost every Sienese painter knew by instinct how to attain. That quality is serenity, the something spellbound we find here. And Giorgione is the last Venetian master to possess that secret. [233-4]Although a British subject, Hutton seems to have spent most of his life in Italy. During World War II he was with the British army as it made its way up the Italian peninsula. He was an artistic advisor whose role was to point out important cultural sites that should not be bombed. As the armies approached his beloved Florence, he warned that the whole city should be considered a museum and not be bombed at all. Fortunately, the Germans evacuated and the city was spared.
A list of his many books can be found on Wikipedia.
*Edward Hutton, Venice and Venetia, London, third edition, 1929, first published 1911.