This section is from the book "The Manual of Phonography", by Benn Pitman And Jerome B. Howard. Also available from Amazon: The Manual of Phonography.
See paragraphs 175 to 182.
Par. 175. - Water, meter, thermometer, trumpeter, rafter, lifter, fighter, waiter, loiter, inviter, swelter, dissenter, winter, voter, de-serter, minister, shatter, remitter, alter, lateral, porter, flutter, fritter, smatter, diameter.
Fodder, shudder, seceder, alder, wander, gender, tender, tinder, hoarder, warder, order, defrauder, deluder, ardor, hinder, cylinder, freeholder, oleander, bewilder.
Par. 176. - Weather, father, grandfather, godfather, forefather, lather, whether, nether, thither, whither, lither, wither, mother, grandmother, godmother, smother.
Par. 177. - Anker, hanker, thinker, franker, rancor, drunker.
Anger, finger, linger, conger, monger, younger, longer, stronger.
Par. 178. - Scamper, damper, hamper, pamper, tamper, stamper, temper, distemper, simper, bumper, thumper, jumper.
Amber, chamber, bed-chamber, presence-chamber, limber, clamber, timber, umber, cumber, encumber, cucumber, lumber.
Par. 181. - Material, materially, entirely, entire, materiality, materialize.
Farther, further, murder, larder.
Par. 182. - Modern, eastern, astern, modernize, northern, subaltern, intern, slattern.
Past tenses of verbs whose present forms end with double-lengths are generally written with half-length double consonants: Watered, loitered, faltered, sweltered, muttered, ordered, weathered, smothered, scampered, simpered, murdered, furthered.
After double-length n, ng and sh, however, past tenses are formed by adding the stroke-d to the form of the present: Entered, wintered, anchored, fingered, shattered, shuddered, engendered.
]Aerometer, barometer, bolter, chronometer, colter, deadwater, enter, falter, fetter, filter, fitter, halter, hexameter, knitter, laterally, latterly, laughter, lighter, literal, literally, literati, litter, liturgy, micrometer, midwinter, mutter, neuter, niter, obliterate, palter, philter, polluter, prompter, Psalter, reenter, Salter, saunter, shifter, shutter, simitar, slater, slaughter, smelter, smiter, sumpter, supporter, tempter, transmuter, unfetter, vaulter, waterlogged, welter.
Asunder, attainder, backslider, boulder, cinder, coriander, defender, disorder, elder, Endor, engender, hazarder, holder, householder, invader, joinder, ladder, madder, molder, nadir, orderly, provender, provider, rejoinder, render, retarder, sender, smokier, sunder, surrender, tender, thunder, upholder, wilder, winder, wonder, yonder.
Anchor, canker, danker, drinker, flanker, lanker, ranker, sinker, tinker, winker, younker.
Altered, bewildered, chambered, cumbered, disordered, distempered, fathered, fettered, filtered, fluttered, hampered, lathered, littered, lumbered, moldered, mothered, paltered, pampered, slaughtered, smoldered, tampered, timbered, unfettered, wildered, withered.
Angered, cankered, hankered, hindered, lingered, reentered, rendered, sauntered, surrendered, tendered, thundered, tinkered, wandered, wondered.
 
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