The following are the more common digraphs of H:—
CH, GH, PH, SH, TH,
BH, DH, KH, LH, NH, RH, ZH,
WH.
The first five are perfect digraphs, a phonic union of parts is effected, and a new sound produced; thus, neither “hat,” with the sound of c before it, nor “cat,” with its vowel aspirated, will give the sound heard in “chat” ∴ C + H is not = CH.
CH has three sounds:—k, (chaos); sh, (bench); and a third, compound, tsh (church).
GH is a digraph to perpetuate the memory of English orthographical anomalies.[[11]] It is used in writing seventy-five words, and in sixty-three of them its presence is ignored entirely; in nine it is equivalent to ff, and in three it represents a g. It signifies nothing in “high,” “Hugh,” &c.; and in “flight,” “night,” &c., it retains the same signification. In Old Saxon, and in Anglo-Saxon, “high” was written hea, heag, hig, heah, heh, hih, &c. A spirit of impartial justice instigated later writers to take in both the g and the h. Professor Meiklejohn (St. Andrews) mentions the opinion held by some, that the Normans would not pronounce gutturals, and disregarded the Saxon terminal h’s, wherefore the scribes attempted coercion by strengthening their Aspirates with a g. The result must have been a failure, since both the h’s and their g-prefixes became lost to the pronunciation of most words. The English words in which GH is an initial digraph are ghastly, ghost, and gherkin; in the two former the H is altogether adventitious. There exists a proneness to transpose the h and the t of height, (Saxon, heath, hihth, &c.), in consequence of which, and with a superfluous d, it becomes “heidth.” This mispronunciation is recorded by Jones as early as 1701. The practice will arise from a natural tendency of the mind to bring into conformity the sounds of words that are associated in their meanings—length, depth, breadth, width ergo: “heidth”!
PH has the sound of f (sphere). In Stephen and nephew it stands for v.
SH is the French j (joli), unvocalised. The Anglo-Saxons had not this digraph, but it appeared some centuries after the conquest, which suggests the possibility of its having been introduced by Norman influences. Some curious philologist may perhaps undertake to substantiate or demolish the theory that the Anglo-Saxons learnt to pronounce SH by attempting to utter the French j. Certain it is that the words Je me jette à genoux would become changed into “Sheh me shett ah sheenoo” by the average German of to-day. The substitution of SH for ss in the word assume produces an odd-sounding archaism, yet one that is occasionally met with in otherwise good speakers. According to Jones, “ashume” was correct speech in the seventeenth century.
TH of thin and TH of then are elementary sounds represented now-a-days by two letters each. The former is produced by passing unvocalized breath through a narrow aperture left between the fore-part of the tongue and the edge of the upper teeth (the central incisors); the second by the same position of the speech-organs, but with breath that is vocalized.[[12]] Common errors are, to confound the TH of bath, path, wreath, &c., with that of bathe, paths, wreathe, &c. The former are unvocalized, as in thin.