‘The Island of Devenish is undoubtedly one of the foremost and most interesting of the Lough Erne Archipelago. As the visitor sails down the lake from Enniskillen, after turning the point of Derrylinch, the Round Tower tops, with the rounded windows and the square Bell Tower of a more modern priory, appear over the Island’s highest ridge towards the south. On proceeding, wooded promontories throw their broad shadows across the still bays; the fair slopes and lawny knolls stand greenly out from the dark sylvan scenery; while the islands seem to be floating, as on a crystal sea, until the tourist reaches Devenish Island. The soil is exceedingly fertile and covered with the rankest and greenest grass. Over this the pilgrim, landing from his well-appointed pleasure-boat will be sure to turn his steps in the direction of various old buildings, lying in proximate position, and yet somewhat separated in some instances. The ruins, which yet remain in their insular situation, are of extraordinary antiquarian interest.’
From Lives of the Irish Saints by the Rev. John Canon O’Hanlon, Volume IX (1873) 

‘One of the most interesting spots in the neighbourhood of Enniskillen, is Devenish Island, with its round tower and other ancient relics. It stands just where the lower lake expands; and is about two miles from Enniskillen. One may visit it either by boat from Enniskillen, or follow the road from the town, and make use of the ferry-boat. The island slopes gently from the water’s edge, in a fine green swell; but is entirely destitute of wood; and is said to contain upwards of seventy acres. The round tower of Devenish is said to be the most perfect in Ireland and, altogether, the finest specimen of these singular structures. The height of the tower is eighty-two feet; the thickness of its walls three feet, five inches; the circumference forty-nine feet; and the diameter, inside, nine feet, two inches. Twelve feet above the doorway there is a window, angularly pointed; and, higher up, another window nearly square. Still higher are the four windows, common in all these towers; and the key-stone above each is ornamented with a human head.’
From Ireland in 1834: A Journey throughout Ireland by Henry D Inglis (1835) 

‘The lower church is dedicated to St. Molush, “who read the planets” we were told; and near it are the remains of an ancient building, called St Molush’s kitchen. In the vicinity is a coffin of hewn stone in which, if the saint found a resting place, he has long since been dispossessed of it, and superstition now ascribes to this stone-bed the power of removing pains in the back. Near the summit of the hill are the remains of the abbey. The centre of the building is an arch resting on four pillars, and supporting a belfry tower, with a winding staircase of good workmanship leading to the summit. An inscription records the date of the erection, and the name of the architect, etc. That which was apparently the northern aisle of the church, is now changed into a stall for cattle, a desecration much resented by the herdsman, a very superstitious and apparently a very devout Catholic who repeated with much zest an observation which had been made to him, that the author of this piece of barbarism would be found to be adorned with hoofs and horns in the next world!’
From The Island of Saints, or Ireland in 1855 by John Eliot Howard (1855)