The strict dependence of writing, indeed, upon the material employed is nowhere better shown than in the case of the Assyrian cuneiform inscriptions.  The ordinary substitute for cream-laid note in the Euphrates valley in its palmy days was a clay or terra-cotta tablet, on which the words to be recorded—­usually a deed of sale or something of the sort—­were impressed while it was wet and then baked in, solid.  And the method of impressing them was very simple; the workman merely pressed the end of his graver or wedge into the moist clay, thus giving rise to triangular marks which were arranged in the shapes of various letters.  When alabaster, or any other hard material, was substituted for clay, the sculptor imitated these natural dabs or triangular imprints; and that was the origin of those mysterious and very learned-looking cuneiforms.  This, I admit, is a palpable digression; but inasmuch as it throws an indirect light on the simple reasons which sometimes bring about great results, I hold it not wholly alien to the present serious philosophical inquiry.

Printing, in turn, necessarily follows the rule of writing, so that in fact the order of letters and words on this page depends ultimately upon the remote fact that primitive man had to use his right hand to deliver a blow, and his left to parry, or to guard his heart.

Some curious and hardly noticeable results flow once more from this order of writing from left to right.  You will find, if you watch yourself closely, that in examining a landscape, or the view from a hill-top, your eye naturally ranges from left to right; and that you begin your survey, as you would begin reading a page of print, from the left-hand corner.  Apparently, the now almost instinctive act of reading (for Dogberry was right after all, for the civilised infant) has accustomed our eyes to this particular movement, and has made it especially natural when we are trying to ‘read’ or take in at a glance the meaning of any complex and varied total.

In the matter of pictures, I notice, the correlation has even gone a step farther.  Not only do we usually take in the episodes of a painting from left to right, but the painter definitely and deliberately intends us so to take them in.  For wherever two or three distinct episodes in succession are represented on a single plane in the same picture—­as happens often in early art—­they are invariably represented in the precise order of the words on a written or printed page, beginning at the upper left-hand corner, and ending at the lower right-hand angle.  I first noticed this curious extension of the common principle in the mediaeval frescoes of the Campo Santo at Pisa; and I have since verified it by observations on many other pictures elsewhere, both ancient and modern.  The Campo Santo, however, forms an exceptionally good museum of such story-telling frescoes by various painters, as almost every picture consists of several successive episodes.  The famous Benozzo Gozzoli, for example, of Noah’s Vineyard represents on a single plane all the stages in that earliest drama of intoxication, from the first act of gathering the grapes on the top left, to the scandalised lady, the vergognosa di Pisa, who covers her face with her hands in shocked horror at the patriarch’s disgrace in the lower right-hand corner.