William Chilton (1815 - 1855) was a strident atheist who co-founded (with Charles Southwell) the atheist weekly, The Oracle of Reason: Or, Philosophy Vindicated, that ran from 1841 to 1843. In this paper, a forty-eight part series on evolution entitled "Theory of Regular Gradation" appeared (pdf here). The first six parts were written by Southwell; but after his imprisonment on charges of blasphemy, Chilton authored the remainder of the series. This set of articles just predates the appearance in 1844 of Robert Chambers' anonymously published Vestiges of the Natural History of Creation and stands in contrast with this later work by virtue of its strictly materialist point of view and overt atheism (Chambers assumed a higher being that set the laws of the universe in motion). Southwell's and Chilton's treatment of evolution also contains some of the crude racist and anti-semitic overtones of the day, for example, the illustration of fossil man accompanying the first essay and the frequent references to the Bible as the "Jew Book." Neither Chilton nor Chambers (an Edinburgh publisher) were practicing natural historians. Rather, they culled their information from the broad scientific literature of the period and reworked it into a general system of evolution or transmutation.
Title page of The Oracle of Reason
To learn more about Southwell, Chilton and the politics of atheism and evolutionism of this period, please read Desmond, A. 1987. Artisan Resistance and Evolution in Britain, 1819-1848. Osiris 3: 77-110. pdf here.
Also, see pages 308-320 of Victorian Sensation, by James A. Secord (2000).