I have been looking at the publishers text on the dust-jackets for the the first four printings of the UK Hobbit.

The first printing (September 1937) contained the following

"If you care for journeys there and back, out of the comfortable Western world, over the edge of the Wild, and home again, and can take an interest in a humble hero (blessed with a little wisdom and a little courage and considerable good luck), here is the record of such a journey and such a traveller. The period is the ancient time between the age of Faerie and the dominion of men, when the famous forest of Mirkwood was still standing, and the mountains were full of danger. In following the path of this humble adventurer, you will learn by the way (as he did)—if you do not already know all about these things—much about trolls, goblins, dwarves and elves, and get some glimpses into the history and politics of a neglected but important period.
For Mr Bilbo Baggins visited various notable persons ; conversed with the dragon, Smaug the Magnificent ; and was present, rather unwillingly, at the Battle of Five Armies. This is all the more remarkable, since he was a hobbit. Hobbits have hitherto been passed over in history and legend, perhaps because they as a rule preferred comfort to excitement. But this account, based on his personal memoirs, of the one exciting year in the otherwise quiet life of Mr. Baggins will give you a fair idea of this estimable people now (it is said) becoming rather rare. They do not like noise.

J.R.R. Tolkien is Rawlinson and Bosworth professor of Anglo-Saxon at Oxford, and fellow of Pembroke College. He has four children and The Hobbit was written for them, and read aloud to them in nursery days, which is of course the way in which practically all the immortal children’s stories have come into being. But the fame of the story spread beyond his immediate family and the manuscript of The Hobbit was lent to friends in Oxford and read to their children. Though they are utterly dissimilar in character, the birth of The Hobbit recalls very strongly that of Alice in Wonderland. Here again a professor of an abstruse subject is at play ; while Alice in Wonderland is full of crazy conundrums, The Hobbit has constant echoes of magic and mythology culled from a wide and exact knowledge. Dodgeson at first did not think it worth publishing his tale of Wonderland and Professor Tolkien—but not his publishers—still remains to be convinced that anybody will want to read his most delightful history of a Hobbit’s journey."

Tolkien wrote in Carpenter #15: Letter from J.R.R. Tolkien to C.A. Furth (Allen & Unwin) • 31 August 1937 (#15) with proposed changes to the blurb which were introduced in the Second printing (December 1937)

" All who love that kind of children's book which can be read and re-read by adults should take note that a new star has appeared in this constellation.. . . . On the edge of a valley one of Professor Tolkien's character's can pause and say 'It smells like elves.' It may be years before we produce another author with such a nose for an elf." — THE TIMES.

If you care for journeys there and back, out of the comfortable Western world, over the edge of the Wild, and home again, and can take an interest in a humble hero (blessed with a little wisdom and a little courage and considerable good luck), here is the record of such a journey and such a traveller. The period is the ancient time between the age of Faerie and the dominion of men, when the famous forest of Mirkwood was still standing, and the mountains were full of danger. In following the path of this humble adventurer, you will learn by the way (as he did) — if you do not already know all about these things — much about trolls, goblins, dwarves and elves, and get some glimpses into the history and politics of a neglected but important period.

For Mr Bilbo Baggins visited various notable persons ; conversed with the dragon, Smaug the Magnificent ; and was present, rather unwillingly, at the Battle of Five Armies. This is all the more remarkable, since he was a hobbit. Hobbits have hitherto been passed over in history and legend, perhaps because they as a rule preferred comfort to excitement. But this account, based on his personal memoirs, of the one exciting year in the otherwise quiet life of Mr. Baggins will give you a fair idea of this estimable people now (it is said) becoming rather rare. They do not like noise.

J.R.R. Tolkien is Rawlinson and Bosworth professor of Anglo-Saxon at Oxford, and fellow of Pembroke College. He has four children and The Hobbit was written for them, and read aloud to them. It became a standing family entertainment, especially at Christmas-time. But the manuscript soon began to go visiting among older and younger friends (there are many lovers of real fairy stories); and the fame of the hobbit spread beyond the family. Though they are altogether dissimilar, the birth of The Hobbit recalls strongly that of Alice in Wonderland and Through the Looking Glass; and here again we have a student at play. There is as little philology in The Hobbit as there is mathematics in Alice; but this play is not an escape from the study — a most attractive room, as most children know who have the chance of invading it.

The Hobbit has riddles, runes and Icelandic dwarves; and though its world of magic and mythology is its own, a new land of lore, it has the atmosphere of the ancient North. Dodgson at first did not think it worth publishing his tale of Wonderland, and it was very hard to convince Professor Tolkien that anyone would want to read his delightful book. The following few extracts chosen from a battery of favourable reviews, will show that leading critics at any rate have sided with the publishers in claiming that The Hobbit is a work of genius.

" The firm of Allen & Unwin have just made, one would have supposed, the rashest claim in the world - namely, that the author of a children's book just published . . . . has certain affinities with Lewis Carroll. . . . Well I am sorry to disappoint the cynics - but this is one of those occasions when the publishers have been justified of their audacity- and fully justified. The Hobbit is a glorious book. . . .No normal child could resist it" — Phoebe Fenwick Gaye in TIME AND TIDE.

" Its place is with Alice, Flatland, Phantases, The Wind in the Willows. . . .Prediction is dangerous, but The Hobbit may well prove a classic."— TIMES LITERARY SUPPLEMENT.

" The Hobbit is pure fantasy. . . . It is grand imaginative stuff . . . . Mr Baggins . . . . is well worth knowing and grows on you."— Howard Spring in EVENING STANDARD.

" This is a quite exceptional book. For colour, for magic there has been nothing like it for years. . . .From nine and ten years old and upwards, to almost any age, it will be loved by all those who kindle the spark of enchantment."— NURSERY WORLD."

The third and fourth impressions however largely used the text from the first impression, but with the spelling of Dodgson corrected.

"If you care for journeys there and back, out of the comfortable Western world, over the edge of the Wild, and home again, and can take an interest in a humble hero (blessed with a little wisdom and a little courage and considerable good luck), here is the record of such a journey and such a traveller. The period is the ancient time between the age of Faerie and the dominion of men, when the famous forest of Mirkwood was still standing, and the mountains were full of danger. In following the path of this humble adventurer, you will learn by the way (as he did)—if you do not already know all about these things—much about trolls, goblins, dwarves and elves, and get some glimpses into the history and politics of a neglected but important period.

For Mr Bilbo Baggins visited various notable persons ; conversed with the dragon, Smaug the Magnificent ; and was present, rather unwillingly, at the Battle of Five Armies. This is all the more remarkable, since he was a hobbit. Hobbits have hitherto been passed over in history and legend, perhaps because they as a rule preferred comfort to excitement. But this account, based on his personal memoirs, of the one exciting year in the otherwise quiet life of Mr. Baggins will give you a fair idea of this estimable people now (it is said) becoming rather rare. They do not like noise.

J. R. R. Tolkien is Rawlinson and Bosworth professor of Anglo-Saxon at Oxford, and fellow of Pembroke College. He has four children and The Hobbit was written for them, and read aloud to them in nursery days, which is of course the way in which practically all the immortal children’s stories have come into being. But the fame of the story spread beyond his immediate family and the manuscript of The Hobbit was lent to friends in Oxford and read to their children. Though they are utterly dissimilar in character, the birth of The Hobbit recalls very strongly that of Alice in Wonderland. Here again a professor of an abstruse subject is at play ; while Alice in Wonderland is full of crazy conundrums, The Hobbit has constant echoes of magic and mythology culled from a wide and exact knowledge. Dodgson at first did not think it worth publishing his tale of Wonderland and Professor Tolkien—but not his publishers—still remains to be convinced that anybody will want to read his most delightful history of a Hobbit’s journey.

SOME PRESS OPINIONS

“ His wholly original story of adventure among goblins, elves and dragons . . . gives . . . the impression of a well-informed glimpse into the life of a wide other-world ; a world wholly real, and with a quite matter-of-fact, supernatural natural-history of its own. It is a triumph that the genus Hobbit, which he himself has invented, rings just as real as the time-hallowed genera of Goblin, Troll and Elf.”
—New Statesman and Nation

“ Professor Tolkien’s finely written saga of dwarves and elves, fearsome goblins and trolls, in a spacious country of far-off and long-ago. . . . This is a full-length tale of traditional magic beings. . . . The quest of the dragon’s treasure—rightfully the dwarves’ treasure—makes an exciting epic of travel, magical adventure, and, working up to devastating climax war.” —Observer

“ A fascinating excursion into the early English scene when the land was possessed by a multitude of elves, gnomes and dwarves, none too amiably inclined to the other. This is a solidly delightful book.” —Times

“ This is good. . . . The Hobbit . . . is the tale of an ordinarily sensible conventional hobbit, who was led away by such riff-raff as dwarfs and goblins into an Adventure, and for reading aloud for the smallest child, and for giving to the eight-year-old to read himself we firmly recommend it.” —Lady

Can anyone point me to any publications that explain why the text was reverted after the second impression? and enjoy reading the press opinions if you have not seen them before