Incidentally, Apollinaire's pictorial poems rarely consisted of just the "concrete" (shaped) part, though from the way they're described and quoted, you'd think the shaped part of the poem was the whole thing. For instance, the concrete poem below that begins "Tant d'explosifs sur le point..." is actually itself only the opening of a longer poem called "Du coton dans les oreilles" (something like "cotton in your ears"). Much of the poem is fairly conventional in form, if still difficult. He continues to explore the possibilities that print offers to verse by, say, using larger font to signify "words" of the bugle call, or by surrounding the words "Les cenobites tranquilles" with a sort of frame, as though what the dugout is called informally among the soldiers were a physical label.
On the whole, the concrete poems are much easier to understand in context, so it's a bit annoying that on Wikipedia (of course) and such those parts are presented on their own, as though each were the entirety of the poem in which it's found.
It's also annoying that if he's known in English at all it's as "the concrete poems guy" when he also wrote many very traditionally-formed poems (though again, they are difficult). In fact, I get the impression (though I haven't counted) that these are actually the majority in Calligrammes.
Here's a lovely example of one of these more traditional ones. The assonance and gentleness of the rhyme are features almost un-reproduceable in English; only Frost and Wilbur really come close.
Un oiseau chante
Un oiseau chante ne sais où
C'est je crois ton âme qui veille
Parmi tous les soldats d'un sou
Et l'oiseau charme mon oreille
Écoute il chante tendrement
Je ne sais pas sur quelle branche
Et partout il va me charmant
Nuit et jour semaine et dimanche
Mais que dire de cet oiseau
Que dire des métamorphoses
De l'âme en chant dans l'arbrisseau
Du cœur en ciel du ciel en roses
L'oiseau des soldats c'est l'amour
Et mon amour c'est une fille
La rose est moins parfaite et pour
Moi seul l'oiseau bleu s'égosille
Oiseau bleu comme le cœur bleu
De mon amour au cœur céleste
Ton chant si doux répète-le
À la mitrailleuse funeste
Qui chaque à l'horizon et puis
Sont-ce les astres que l'on sème
Ainsi vont les jours et les nuits
Amour bleu comme est le cœur même