In the Middleton Book in his early years in the village he had written out a "Catalogue of Books", which appears to be a record of his library.
It naturally included the classical authors and a range of religious works, such as Hebrew grammars, a Hebrew Psalter, sermons, commentaries, and Waldo on Liturgy , but also poetry and French authors such as Pascal, Racine and Mme de Sévigné, together with dictionaries. There were also works by the Evangelical philanthropist Hannah More, who had sought to counter the arguments of Tom Paine (the author so admired by the radicals of Stokesley) with her Cheap Repository Tracts urging the poor to work hard, respect the gentry and trust in God – views echoed in Barlow's sermon of 1833.
However Mr Barlow, though classically educated, was not interested in the usual pursuits of the scholarly Victorian cleric.
He had little interest in theological debate, and the great questions of his day that had tormented so many – from the Tracts for the Times to Essays and Reviews – seem to have made little impression upon him.
Practical matters and technology fascinated him above all, and, as can be seen in the draft of a letter  entitled "Suggestions upon the construction and armour of ships of war", his preoccupations were not those normally expected of Victorian clergy. The letter must date from the mid-1860s, as the Armstrong gun itself was only introduced in 1859:
My Lord Duke. Having carefully studied the experiments lately made at Shoeburyness upon the Hercules target which resisted a 300lbs shot propelled by a 60lb charge target coated with 9in armour backed by wood and iron the bolt having merely penetrated the 9in plate … and finding that such target resisted a 300lb Armstrong gun with a charge of 60lbs of powder …
… bearing all this fully in mind I am of opinion that the plan I now submit to your Grace will in several respects be found superior to the Hercules target. On the other side I give the sketch of a ships side from which it will be seen that my plan is to reduce the vital part of a ship to a minimum and to surround that portion with an impregnable belt …