But the chief importance of his present essay consists in the light it throws for the first time on the nature of the ideograms. The earliest inquirers leant to the opinion that the language was at least partly monogrammatic, though Grotefend was inclined to regard these signs more in the light of abbreviations. He, however, distinctly pointed out the existence of ideographic characters in the shorter inscriptions at Persepolis. In 1846 (December) Hincks recognised a sign that was used ‘by abbreviation for the word “god”’; and he noticed that ‘besides having a phonetic value, it is used as a non-phonetic initial before the name of Ormuzd.’ In the same essay he gave numerous other instances of the existence of ideographic and non-phonetic determinative signs.[808] In 1849 he added for the first time the true phonetic value (_an_) for the sign for ‘god’;[809] and in the present essay he shows the various uses to which ideographic signs may be applied. He explains that many phonetic characters also express words; these may be considered as abbreviations, though possibly some ‘originally denoted ideas and thence, in process of time, the initial sounds in the words which express them.’ A second class resemble the mixed signs of the Egyptians: they may represent words by themselves, but they sometimes require the addition of complements. Another class never have complements, nor any phonetic value except in compound nouns, of which the word they represent forms an integral part. The ideograms, however, that give rise to the most interesting speculation are those that have phonetic values, but where the words that denote the ideas they express have no phonetic relationship to the phonetic value of the ideogram. For example, we now know that the phonetic value of the ideogram for ‘god’ is _an_; but this syllable forms no portion of the Assyrian word for ‘god,’ which is _il-u_. A glance over any table giving the syllabic values of ideograms will show how extensively this peculiarity prevails; and its recognition soon led Hincks to the important deduction that the writing was borrowed from some other people where the phonetic value of the ideograms was in some sort of agreement with the initial sound of the word they represented.[810] Hincks dwelt on the great difficulty of deciphering a language in which the characters are sometimes used as phonetic syllables and sometimes as ideographs. In each case it was necessary first to determine in which sense it occurred, and, if in the latter, the pronunciation could only be ascertained when it was found spelt out phonetically in some known word. For example, the pronunciation of the ideogram for ‘god’ was fixed by finding that it formed the _il-u_ in ‘Bab-ilu.’ When the pronunciation of the ideogram was known, it afforded, as has been said, in the majority of cases no clue whatever to the syllabic value of the sign, and the transliterator was liable to fall into the error of reading