Compression as a phonetic term

The term compression in its phonetic sense denotes the reduction of articulatory movements leading to

• a reduction of diphthongs plus schwa to diphthongs or monophthongs,
• a reduction of diphthongs to monophthongs,
• a change from a monophthong to an approximant, 
• a change from one vowel class to another or 
• coalescence. 

When was the term first used? The OED remains silent. It was by mere chance that I found a fairly early mention of the term in Notes on Spelling Reform of 1881 by W. R. Evans. On p.11 we read this:

During all the time occupied by these changes - the shifting of vowel-sounds step by step along the scale, the expansion of simple vowels into diphthongs, and the compression of diphthongs into simple vowel-sounds - the written form of the language remained nearly stereotyped as regards any indication of such changes, [...]

For earlier uses of the term it may be worthwhile to check "The Phonetic Journal", which was published from 1873 to 1905. It's a pity I don't have access to this journal.

BTW: I couldn't find anything on this W. R. Evans. The ODNB has but an entry on a clergyman by the same name. If any of my followers can enlighten me, I'd be most grateful.