One of our favored public domain translations of Lucretius is an anonymous prose translation published by Daniel Brown in London in 1743.
As a matter of idle speculation, I thought there might be some interest in trying to identify the responsible party. The two main approaches that occur to me at the moment are to a.) Locate individuals from that time period who display an interest in Lucretius, and b.) Review other contemporaneous translations of Latin authors for signs of similarity.
This is very much an exercise of throwing things against the wall and seeing what sticks, so with that in mind I present my first contender;
From wikipedia: His father translated a portion of Lucretius (the plague in Athens) for Thomas Creech¹ in verse, and his brother translated five books of Paradise Lost into Latin. After 1740 when he finished Virgil, no major work is listed. This gives him three years to complete Lucretius, alongside his clergy work and poetry.
¹I had no idea Creech had a contributor!