Aerial view of probable site of Ark's Weir


1909: Ark Weir in The Stripling Thames by Fred Thacker

Ark's Weir or Ark or Hart's or Ark Island Weir.
1920: Fred Thacker's Map shows the site quite clearly -

Ark's Weir Map
The site of Ark's Weir above Bablock Hythe.

I had originally identified Hart's Footbridge above Northmoor Lock as the site of the following story - however Julie Godson, in her book "The Water Gypsy" has identified Noah's Ark Island and Weir - and so I have transferred the details I have -

The Water Gypsy by Julie Ann Godson

At dusk on a snowy March evening in 1766 a tired young couple made out the welcoming lights burning in the windows of the creaky old Berkshire manor house that was to be their home.
He was William Flower, Viscount Ashbrook, she was Betty Ridge, daughter of a humble Thames fisherman. Earlier that day they had been married in a little village church in Oxfordshire, and now Betty was embarking on a new life in the alien world of the aristocracy. But the challenges she would face would prove far greater than she could have imagined.
Based on the author's original research, The Water Gypsy traces the untold story of Betty's struggle as a young widow to protect her children's interests in the hostile climate of 18th-century Ireland, and her son's ultimate triumph at Windsor Castle and St James's Palace. It was a project which culminated in the most glittering marriage in the entire history of the Ashbrook family when Betty's granddaughter became Duchess of Marlborough and chatelaine of Blenheim Palace.
ISBN: 9781784075545 Total Pages: 206 Published: 26 March 2014 Price: £9.99 Amazon

[Source: "The Thames Highway" Vol 2 p.80, Fred Thacker 1920]

William Flower, Viscount Ashbrook, was an undergraduate at Oxford who came one day to fish at what was then probably known as Rudge's Weir.  And there he fell in love with the weir keeper's daughter, Betty Rudge.  He was determined to marry her, despite the enormous social gulf between them, and sent her away to be educated. 
They eventually married quietly in Northmoor Church in 1766 when he was 23 and she was 19.
He died aged 36. His epitaph in Shellingford Church ends with these lines -

He was a kind and affectionate husband, father and brother,
In him the Rich had lost a sincere and disinterested Friend,
The Poor, a compassionate and generous Benefactor.

Betty, or Elizabeth, as she was then called, outlived her husband by twenty eight years. She died on the 23rd February, 1808 -

universally lamented in the 63rd year of her Age.

Thomas Ridge (Rudge?) was the weir keeper. [The story below calls him John]
His daughter became a Viscountess. 
Two grandchildren became Viscounts. 
His great grandson became a Viscount. 
His great grand daughter became Duchess of Marlborough on her marriage to Sir Winston Churchill's great grandfather: -
Thomas Ridge had a daughter Elizabeth Ridge baptised 3 August 1745.
Elizabeth Ridge married William Flower, 2nd Viscount Ashbrook on 20 March 1766 when she was 20. She became Viscountess Ashbrook on her marriage.
William & Elizabeth Flower had two sons, William & Henry:
William Flower, born 16 Nov 1767 and baptised 25 October 1767. On his father's death on 30 August 1780 he became 3rd Viscount Ashbrook. He died on 6 January 1802.
Henry Jeffery Flower was born 6 November 1776 and baptised 17 November 1776. He became 4th Viscount Ashbrook on his brother's death on 6 January 1802.
Elizabeth Flower nee Betty Ridge married again on 20 January 1790, the Revd Dr John Jones. She died on 23 February 1808.
Henry Jeffery Flower married Deborah Susannah Friend on 26 May 1802. They had five children. She died 24 March 1810.
Henry Jeffery Flower then married Emily Theophila Metcalfe on 22 June 1812 and they had a daughter Hon. Charlotte Augusta Flower born on 25 November 1818.
Hon. Charlotte Augusta became Duchess of Marlborough when she became the second wife of Sir Winston Churchill's great grandfather, George Spencer Churchill, 6th Duke of Marlborough.
As for lock keepers, to paraphrase the King James Bible:
"Be not forgetful to entertain lock keepers: for thereby some have entertained aristocrats unawares!"

1860: Ridges Weir, Henry Taunt -

Ridges Weir, Henry Taunt, 1860
Ridges Weir, Henry Taunt, 1860
© Oxfordshire County Council Photographic Archive; HT1149

1920:  Fred Thacker -

It is now a very picturesque scene.  Close by, on the Left bank,
[just discernible in the 1910 photograph above, between the willows and the tall reeds]
is an ancient thatched house of some size, which may have been the weir keeper's.  The bridge crosses at the exact point at which the river ascends northwards for its long sweep round by Oxford and thence southward to Abingdon:  only six miles away as the crow flies, although some twenty-four by water.

1907: Romantic Stories of Famous Families (from a New Zealand National Library web page in Maori!) -

"In the very nick of time, Festing my boy! Here she comes, and - by Jove! if it is not actually a 'she'! - No grim Charon to ferry us over the Styx this time; but, unless my eyes play me false, a maiden with the form of a sylph, and I dare swear, when we see it, a face as bewitching as her figure."
The two young men, fishing-rods in hand and with the day's spoil in baskets slung over their shoulder, stood on the bank of the Isis, silhouetted against the golden glory of the setting sun, while the punt, with its solitary passenger and its fair ferry-maid, nosed its way across the river towards them. A few moments later the passenger was stepping on shore, and a sweet, flushed face was looking up at the young men on the bank, only to turn away in coy confusion at the ardour of the glances that met hers.
"Didn't I tell you, Festing?" whispered the taller and handsomer of the two youths to his companion.
"I knew that figure had a face to match its beauty. Gad! If I don't believe it's Amy Robsart come to life again to steal our hearts away.
" he continued, with a sweep of his gold-laced hat and a courtly obeisance,
"may two unworthy wights have the honour of your company to the opposite shore?"
"If you please, sir," the maid answered, with a demure curtsey and downcast eyes,
"that is what I am here for."
"And indeed, madam, your presence is an honour for which we were little prepared, but which we highly esteem," answered the young gallant, as he followed his companion into the boat.
"But you must allow me the privilege of being ferryman"; and, taking the pole from her hands, he pushed off from the shore.
Never in the history of the Northmoor ferry had the distance been so long or seemed so short from bank to bank; and never surely has ferryman proved so incompetent or required so much instruction. When at last the opposite bank was reached,
"I vow, my dear lady," he said, "I am so fatigued by my exertions that I must rest awhile before resuming my journey to Oxford. Before I go, may I inquire the name of the fair maiden who has brought so much sunshine into the close of a rather dreary day?"
"My name, sir, is Betty Ridge," was the demure answer.
"Some call me 'Elizabeth' but I love 'Betty' best; and my father, who is the ferryman, has had to go to Oxford, so I have had to take his place."
"Indeed, Mistress Betty, I must make the acquaintance of your father to congratulate him on having such a lovely daughter. Don't you know, child, how beautiful you are?"
"Oh, fie, sir!" the maid answered, as the crimson flooded her cheeks; "you would not say that if you could see my sister; she is beautiful if you like."
But already the sun had sunk below the horizon, and, as darkness was falling swiftly over the land, there was little time left for the paying of mere compliments; and with farewells and with promises to return again soon to make Mistress Betty's better acquaintance, the two young men resumed their tramp towards Oxford.
Such was the opening scene in one of the prettiest romances in the history of our peerage; though as yet the ferry-man's fair daughter little dreamt of all that was to follow that chance meeting on the Isis, over which the setting sun threw its glamour. Betty knew nothing of the young gallant whose admiring glances and flattery had made her cheeks flush and her heart go pit-a-pat; but shoe knew that between her and him there was a great social gulf. He was obviously a gentleman; she was a peasant's daughter, and she was too sensible a girl to attach much importance to the pretty speeches of a man so much above her.
And the young gallant himself, we may be sure, was equally unsuspecting of the trap Cupid had laid for his undoing. The son of a Baron and a Viscount, he had in his veins the blood of a long line of distinguished ancestors. Before the Conqueror stepped on our shores there were Flowers in England who were men of high rank and large possessions.
One of his ancestors had been Knight of the Shire and Sherriff of Rutland in the far-away days of the second Richard, and as Speaker had been the first commoner in the land; another had been a great general in Ireland and Governor of Dublin, and so on, down the long list of his forefathers, until William Flower, his grandfather was ennobled as a Baron of Castle Durrow, a title to which his father had added that of Viscount Ashbrook; and to these honours, as well as to vast estates, young William Flower, gentleman-commoner of Magdalen College, would one day succeed. His ancestors had sought their brides among the daughters of noble families, and he in his turn would be expected to woo and win a bride with equally blue blood in her veins.

But long descent and blue blood notoriously count as naught in the eyes of Cupid, who had matched against them the charms of the lowly-born Betty Ridge, whose "milk and roses," blue eyes, and wealth of rippling hair were more potent spells than all the blood of the Howards.
Nor was it long before the spell began to work, for the very next day, young Flower, fishing-rod in hand, found himself once again at the ferry; and once more Cupid seemed propitious, for Betty, looking more radiantly beautiful than ever, was standing, framed by the rose-covered porch of the cottage, as if awaiting his coming. But if she felt any pleasure at the sight of the tall, handsome fisherman, whose eyes and tongue had already begun to play such havoc with her peace of mind, she gave little evidence of it.
"Good morning to you, Mistress Betty," was his greeting.
"I vow you look sweeter than ever in the freshness of the morning."
"You should not say such things," Betty flashed out, flushing hotly,
"and I don't think you would if my father were here. It is not wise for a gentleman to pay such compliments to a poor girl like me."
"But Betty, if I mean them," protested the young man,
"as I vow I do?"
And her father coming up at that moment, she walked indoors, and not another glimpse of Betty did Mr Flower see that day or for many days after.
If Betty, instead of being a simple rustic maid, had been an accomplished coquette, she could not have done more to fan the flame of her lover's passion. Her maidenly modesty inspired his respect, which must always be a factor of true love; her coldness hardened his resolve to win her favour. Day after day he made his way to the ferry without even catching a glimpse of the fair young face that haunted him day and night, until at last his opportunity came - as it always does to the patient wooer. And this time he succeeded in convincing her that his worship was sincere.
"I love you Betty," he said, in a voice trembling with the sincerity of his passion;
"and your coldness drives me to distraction. I vow you are far dearer to me than all the world. I cannot bear the though of life without you. Cannot you give me just a little love in return?"
Betty drooped her beautiful head, but made no answer.
"I have little to offer you at present," he continued,
"but some day I can make you a great lady, as you are now and always will be queen of my heart."
"Ah," Betty said at last, as she looked timidly up into her lover's face;
"that is it! You are a gentleman and I am but a poor little nobody. How can I know that if you make me your wife you will not despise me instead of loving me?"
"I swear it, Betty, I swear it! Cannot you trust me when I say that as my wife you will be dearer to me than ever? Say that you love me and that you trust me!"
What maiden could resist such pleading? Certainly not Betty; for from the first her heart had gone out to her handsome young lover, and try as she might and did, she could never recover it. And then at last she confessed that she did love him, "just a little"; and thus it was that troth was plighted between the Viscount's son and the peasant-maid on the banks of the Isis, a century and a half ago.
[Now two and a half centuries ago]
It was only after Mr Flower had won his bride that he revealed to her his rank and the position she would some day fill as his wife and lady of the castle of Durrow. But startling as the revelation was, Betty had no fears for the future. She had given her heart, and with it her absolute trust; and she determined that her husband should never have cause to blush for her even as a Viscountess and chatelaine of a castle. As for plain, honest John Ridge, he was delighted at the good fortune that had befallen his favourite daughter. William Flower had quickly got into the good books of the ferryman, who often declared,
"He's a fine gentleman, but he's got the right ring."
Then followed halcyon days for the affianced pair, who tasted the full delights of "Love's young dream". Betty's great desire now was to fit herself for the exalted position she was one day to fill as her lover's wife; and with this object she was placed under the charge and roof of a lady who lived a few miles away, and who trained her in all the ways and accomplishments of refined society. To this retreat, Mr Flower, who was now an ensign in the army, often found his way, noting with pride the development of the sweet flower of girlhood he had made his own, and, indeed, prouder of his humble lady-love than if she had been the daughter of a belted earl.
For three years Betty remained under tutelage, growing daily to a ripe and perfect beauty of mind and person; and then came that glad day, the crown of her happiness, when the gallant soldier, now a Viscount and a Baron, led to the altar the blushing and radiantly-lovely daughter of the ferryman.
Of her later life this is not the place to write. Let it suffice to say that, as Viscountess Ashbrook, she proved worthy of her husband's highest expectations, playing the role of a great lady as if to the manner born, and winning all hearts by her unaffected charm and charity.

Sighs ...

1794: Boydell: almost certainly talking of Ark's weir -

On approaching Hart's Weir the banks are so thickly planted that the river appears to be passing through a wood whose trees overarch the water.  Here the Thames divides itself into one large and two lesser streams, forming as many islands;  one of which is inhabited.
  The weir stretches across from the meadow bank to these islands, and is a principal feature of one of those home scenes, which frequently afford a more complacent delight to the mind than the wide expansive variety of distant prospect. 
A range of flood-gates crosses the larger current;  while the diminutive streams that divide the islands, tumble over their sluices in unbroken waterfalls.

1832:  Fearnside -

Here the banks become more wooded, and the river is divided into three separate streams;  between the two broadest is an ait, with a pretty rustic cottage.  On one side is the sluice, through which the water, having attained more body, rushes with considerable noise;   another branch flows through the open weir, and a third forms a backwater.

1851 & 1853: not used: gone to decay.
1885: The Royal River -

... Ark, or Noah's Ark Weir ... of the very simplest kind ... performs its service independently of a lock. The object of this simple form of weir is to dam the river to the required height for such purposes as mill heads or navigation.
The business is accomplished by the working of flood gates or paddles in grooves, and between rymers, to the sill at the bottom.
In winter there may be a swift stream through the weirs, but, the weir paddles being withdrawn, there is very little fall.
Shooting the weir stream - one of the adventurous feats of the upper navigation - is an amusement unknown below Oxford, and at times it is not without its risks.

[See also Langley Weir (Farmoor), to which this passage also refers.]
1866: remains of an old weir.
1909: The Stripling Thames, Fred Thacker -

Ark weir (Noah's Ark), known aforetime also as Hart's, once stood about half a mile above Bablock Hithe. ...
The River is now very beautiful for a mile before you reach Northmoor lock, particularly one little straight reach bordered with high, overarching trees, illustrated in Boydell.
Along here if you have good fortune you may hear in the evening the bells of Appleton, and may recall de Quincey: "The music from a finely toned set of bells, when heard upon a winding river, in summer, is the most pathetic in the world".

1920:  Fred Thacker:

The timbers [of Ark's Weir] probably lapsed peacefully away, with occasional assistance from the authorities.
Exactly what constitutes the charm of this place is a little difficult to define, but it is assuredly full of a strong allurement that lingers in the memory.
  The lace-like fall of foaming water has disappeared which so charmed these elder men;  but even so, perhaps because you remember it was once there and entailed so much ancient busyness, the attraction still remains. 
The pool is large, but not so large as at Skinner's.  The chief island is at first scarcely distinguishable from the main land;  as the little eastern channel which nominally insulates it, quitting and rejoining the mainstream beneath white towpath bridges, is now in dry seasons almost empty.  There it still is, however, on the Right bank;  and the third, almost grown up, is still discernable on the right;  while broad and living Thames still runs between.
The island is large and oval shaped.  Four elms tower towards heaven at its lower end;  and close by a large thorn leans over the stunted brick wall of the old weir keeper's cottage.  Leans, I say;  and indeed so it did when I first landed to view it in August 1910.  But as I returned a week later a cart was busy removing the brickwork;  and only the shallow hollow remained beneath the bush.
  Immediately adjacent the ancient stone foundation of the weir beam is still plain to see in the turf of the bank.

My contribution is to identify this site as the most likely candidate for the setting of Robert Bridges' great poem 'There is a hill beside the silver Thames'. Before you make too much fuss about that - see the last verse
"Where is this bower beside the silver Thames? ...
No sharer of my secret I allow ...

1909: Fred Thacker places this poem slightly further downstream in his The Stripling Thames
Listen to 'There is a hill beside the silver Thames'

There is a hill beside the silver Thames,
Shady with birch and beech and odorous pine,
And brilliant under foot with thousand gems
Steeply the thickets to his floods decline.
Straight trees in every place
Their thick tops interlace,
And pendent branches trail their foliage fine
Upon his watery face.
Swift from the sweltering pasturage he flows:
His stream, alert to seek the pleasant shade,
Pictures his gentle purpose as he goes
Straight to the caverned pool his toil has made.
His winter floods lay bare
The stout roots in the air:
His summer streams are cool, when they have played
Among his fibrous hair.
A rushy island guards the sacred bower
And hides it from the meadow, where in peace
The lazy cows wrench many a scented flower,
Robbing the golden market of the bees.
And laden branches float
By banks of myosote;
And scented flag and golden fleur-de-lys
Delay the loitering boat.
And on this side the island, where the pool
Eddies away, are tangled mass on mass
The water-weeds, that net the fishes cool,
And scarce allow a narrow stream to pass:
Where spreading crowfoot mars
The drowning nenuphars,
Waving the tassels of her silken grass
Below her silver stars.
But in the purple pool there nothing grows,
Not the white water-lily spoked with gold:
Though best she loves the hollows, and well knows
On quiet streams her broad shields to unfold:
Yet should her roots but try
Within these deeps to lie,
Not her long reaching stalk could ever hold
Her waxen head so high.
Sometimes an angler comes and drops his hook
Within its hidden depths, and 'gainst a tree
Leaning his rod, reads in some pleasant book,
Forgetting soon his pride of fishery:
And dreams, or falls asleep,
While curious fishes peep
About his nibbled bait, or scornfully
Dart off and rise and leap.
And sometimes a slow figure 'neath the trees,
In ancient fashioned smock, with tottering care,
Upon a staff propping his weary knees,
May by the pathway of the forest fare:
As from a buried day
Across the mind will stray
Some perishing mute shadow, - and unaware
He passeth on his way.
Else, he that wishes solitude is safe
Whether he bathe at morning in the stream:
Or lead his love there when the hot hours chafe
The meadows, busy with the bluring stream;
Or watch, as fades the light,
The gibbous moon grow bright,
Until her magic rays dance in a dream,
And glorify the night.
Where is this bower beside the silver Thames?
O pool and flowery thickets, hear my vow!
O trees of freshest foliage and straight stems,
No sharer of my secret I allow:
Lest ere I come the while
Strange feet your shades defile;
Or lest the burly oarsman turns his prow
Within your guardian isle.

1951: Edward Ardizzone -

Warm and sunny.
We idle most of the day in a pleasant backwater.
Our meals made interesting if somewhat hazardous by a party of voracious swans.
Shop in Northmoor in the afternoon then drop down for a short way to find a good camping ground among some willows.
We pitch the tent and light a wood fire on which we cook our supper and sit round it in the dark.