Preparation:  Discuss in a group, or with your teacher, the meaning of poetic form.
Whenever poets or critics discuss 'free verse' they usually focus on this relaxation of form by the poet, or on the apparent absence of form. They look for form that is present in some subdued or 'organic' way. Free verse (or vers libre, from the French) is certainly a move away from traditional or conventional forms such as the sonnet or ballad. It suits a great many modern poets, who prefer to explore rhythms and scansions that are more personal, more flexible. They want to discover, poem by poem, forms appropriate to their voice and the particular subject of each poem.
I sometimes refer to free verse as 'using ragged lines'. It's my tongue-in-cheek way of making a more serious point about the dangers of free verse. The misunderstandings. For a start, it can get lazy. Anything goes. Form can be overlooked or given only cursory attention. Now, I'm not saying that poems can't 'splurge'. Some of the greatest poets have, in some sense or other, splurged. What I'm saying is that, actually, composing in free verse needs a really sharp ear and an experienced eye. You don't have the scaffolding of an established form to climb up - so you have to have, instead, an incredible sense of linguistic balance. An acute sensitivity to the more subtle aspects of form, rhythm and the arrangement and length of lines.
Spatial form is one such aspect. It's rarely given much thought in the study of poetry. I developed the idea because I believe the eye (as opposed to the ear) is far more interested in space than it is in metre or rhythm. Behind and beyond the sound of that inner voice we use when we read, our eyes are busy registering the shapes made by poems on the page - the promontories and vacancies of words, lines and stanzas. That's why our eyes can instantly tell apart (most) poems from (most) prose, without having to read a word of either. Usually, we can simply see (from the way it's laid out) whether something is a poem or a piece of prose.
Well, I think you probably knew that already! So, why all this fuss? What's so special about spatial form? One way to begin to answer that, is with a simple exercise. First, make a transparency of a poem on clear plastic or acetate (you might need a teacher's help with this). You can use a poem on the syllabus, but not one you've read or studied. The exercise works better (and is more revealing) if you don't yet know what the poem is about. Now place the transparency on an overhead projector and quickly 'de-tune' the focus - i.e. blur the text, slightly, so you can't quite read it. What you should see is a clear but unreadable shape (see Figures 1 and 2).
In a sense, you are now looking at the poem's spatial form. It's astonishing just how much information can be carried by that shape. To see what I mean, simply ask yourself and other members of your class how you react to it. Some students, for instance, point to a sense of uncertainty, or raggedness, in some poems. Others pick up on a 'martial' or obsessive quality, usually if there are ordered ranks of lines or stanzas. That last observation shows how spatial form and conventional form can be linked. It's probably true, for example, that most traditional sonnets will look rather similar when viewed on the overhead projector; many modern poems, however, will not. That's one reason, I believe, why spatial form is now important: because the way poets are arranging their poems on the page has become a complex (though key) aspect of what they want to say to us. Still unconvinced? Well, for the time it takes, why not give it a try?
Activity 1:   Look at Figure 1.  What is the blurred poem 'saying' to you (if anything) through its shape?
Shadow-development
Once you tune into spatial form, the discussions can get quite involved. Sometimes, students can 'see' the emotional or psychological development of a poem, simply through its changing shape. I call this the poem's 'shadow-development' (or sub-textual shadow). But don't get worried (when you eventually do read the poem) if your thoughts on its spatial form or shadow-development took you in a very different direction from the poem's actual message. That's okay. It doesn't mean you've got it wrong. In fact, you might have spotted something interesting. What if, for instance, the poet is using the visual clues of spatial form (either consciously or unconsciously) to undermine the poem's content? Why might they do that?
Activity 2:
  First, repeat Activity 1 using the unfocussed poem in Figure 2.  Now look at the way the shape of the poem develops.
Spatial Form: the Outs and Ins
I hasten to add, these first two activities certainly don't define what spatial form is; nor do they exhaust all the ways you might talk about it. Spatial form is a new idea - I don't want to surround it in its cot with technical definitions or sets of things you have to search for so you can tick them off on a list. I'd much rather you experienced the poem's shape, then responded to it, both intellectually and intuitively. Decide for yourself what spatial form means. I think, though, you will get the gist of it from the above activities, which should draw out at least some of the key elements. I hope, too, you'll discover that spatial form (however you choose to understand it) can sometimes communicate with the reader quite effectively.
Activity 3: 
In groups, or with your teacher, study Figures 1 and 2. 
Make a list of characteristics you think are important to spatial form.
First of all, spatial form is just another tool. It's not meant to replace all the other ways of appreciating, studying, looking at poems. If it doesn't help, move on. But it might just give you a crucial, or unexpected, insight into the poem's intentions or structure.
Secondly, spatial form helps us to examine, closely, one of the poem's most mysterious and fascinating moments: that moment we turn the page onto a poem, and recognise it as a poem. At that instant, we haven't yet started to read. We haven't broached the poem's linear sequence of words. Our typewriter-carriage brain is not yet enabled. The poem hovers there, as an aggregation of geometrical lines and symbols set against white canvas. Before it can flare into comprehension, it must first present itself to us (albeit instantaneously) as a primal, patterned bulk on the chalky cave-wall of the page. In fact, most poems (unlike the majority of prose) are mostly the blank of canvas or wall. This is the instant in which we see the poem as a whole - as a 'Gestalt'. It is a crucial moment, because it can frame how we take the poem in. It's a bit like love/ hate at first sight; or the way some people make a powerful first impression on us. It colours, for us, everything they subsequently do.
Thirdly, it's only part of the story to say that a page of poetry is - initially - usually taken in as a whole. In our eyes' hunt for meaning, there are also many 'local' features of spatial form. One such feature is the visual impact of typeface. Some poems just look wrong in certain fonts. Then there's the visual texture created by the letters themselves. This can come to the fore in poems heavily structured by alliteration, assonance or some other sonority. For instance, look carefully at the lettering in Dylan Thomas's poem: Do Not Go Gentle Into That Good Night. Can you see its typographic 'nap' - i.e. those patterns in the letters, like the fibres in velvet or on a snooker table? What about that visual tension between the lines' long vowels and their terminating consonants? Line-endings, as well, make a crucial local contribution to the spatial energy of a poem. True, they can signal a pause in the thought, or where to take a breath. But they tell us much more than how our lungs should breathe the poem; line-endings are intimately concerned, too, with how the eye 'breathes' it. There is, we know, a natural iambic heartbeat in speech and breath; but it's also worth considering (particularly in such a visual age as ours) that more erratic heartbeat of the scanning eye.
Finally, spatial form doesn't just switch off when we start reading a poem. Why should it? I believe it's like a ghost, shaking its chains down the corridors of every line. And it's precisely where there isn't any obvious or conventional form (as in free verse) that spatial form can take over. Concrete poetry gives a good, though extreme, example of this. At its most banal, concrete poetry will make a poem about a fish - well - look like a fish; though, of course, it can be far more subtle and intelligent than that. I only mention concrete poetry at all, because it provides absolute and obvious proof that spatial form does exist, that it can add information to a poem. What I hope, however, is that the above activities have convinced you of a little more than that: namely, that spatial form is at work, at some level, in all poetry. Even where a poem is completely regular or visually 'uninteresting' on the page, that still tells us something. Maybe it serves to calm us, or encourages us to accept the poem as 'proper' literature; perhaps it helps to set up some kind of expectation, or repetition, or passivity, in our minds. In any case - whether what we're reading is precisely metred or in free fall - the murk of spatial form will haunt us even as we delight in the poem's most brightly-lit parts.
Part of a talk first delivered at the 'Words by the Water' Cumbrian Literature Festival, March 2004.
 
Figure 1. From 'Shadow', in: Heavy Water: a poem for Chernobyl by Mario Petrucci [Enitharmon; £8.95, ISBN 1-900564-34-3]. The text can be found below.
Figure 2. Poem entitled 'Couchette', in: Shrapnel and Sheets by Mario Petrucci [Headland; £6.95, ISBN 0-903074-92-3]. The text can be found below.
Author's note. The use of my own poems in the figures is nothing to do with ego, but to avoid copyright problems. By all means substitute suitable poems of your own choice. Here are some productive alternatives, with a few observations:
(a)  Philip Larkin, For Sidney Bechet. After its pitter-patter heartbeat of fairly regular tercets, the poem's closing couplet suggests something cut short.
(b)  Sylvia Plath, The Fearful. The hourglass shape (albeit sliced in half, Damien Hirst style) reflects the shifts in emotional intensity through the poem.
(c)  Ken Smith, Fox Running. The line-lengths in the opening few stanzas generate a kind of 'spatial acceleration' before adjusting themselves into a regular trot.
 
 
 
         they were dry and folded.
             awake.   Saw her slow shape
               pass a shoulder-bone of wall.
                 shadow-boxing the dark.
               the key in the door so
           sure   -  even now   -  if that
       the boy.   Outside was all
   to give him.   Nothing.   Just  
 
   
For creative writing tutors and schoolteachers. spatial form
Mario Petrucci invents a new and exciting way of looking at form in poetry.
What is meant by 'metre'? Or 'iambic rhythm'? What is 'concrete poetry'?
What do you understand by 'free verse'?
Plunder some favourite poetry to find good examples of each.
Whatever you do, don't read the actual text of the poem (given at the end of article) until you've had a good chance
to brainstorm and share impressions.
Is there any 'shadow-development' in the poem?   When you've discussed this fully, read the text of the poem (see end of article).
Compare and contrast the shadow-development with the actual message of the poem.
For instance,
the raggedness or regularity of the lines and stanzas; the thinness or fatness of the poem;
the use of left or right justification,
indents; and so on. 
In your opinion, is spatial form a useful idea?
I'm entirely happy if your answer to Activity 3 is a resounding 'no' - as long as you have your reasons. I wouldn't blame you, for instance, for feeling that spatial form is a pretty blunt tool for examining poems. Its characteristics aren't very well defined, and the interpretation of those characteristics is rather subjective. There are obvious limits to how much it can tell us: insights are usually quite general, and you might disagree over what those are anyway! There's a real danger of reading far too much into what is, after all, just a shape. So, why bother with it at all? Let me try to answer that in a few different ways.
TEXT behind FIGURES 1 and 2 follows:
SHADOW
She came.    I just know she
    came.    At nightfall I'd place
           her pillow.   Each morning
               I contrived once   -   to stay
                   cast by the moon.    Saw it
                     His cot.   Those tiny fists
                     I called her   -   but had left
                  she vanished.    I can't be
               first small cry came from
moon and snow. And nothing
my thumb to suckle.
- Mario Petrucci
 
 
COUCHETTE
Summer. Dreary Calais
left behind - and the day.
Through half-sleep crescents I see
print on white fluorescence: "Lyon".
Heat. Flesh merged with air I am
this entire cabin, the interminable sliding
of doors. Sweat. The thirst for merest breath
of cool. The window is my mirror. Hard
to swallow. Jolted through the dark
through the struck anvil of junctions
to eventual
sleep
to turn up
in morning green, among mountains
rearing up from the glass-blur. Alps. Whitefaced
chalets flash between limestone, sudden
tunnels channel an ache for light.
Then the gradual withering
of grass to embankment straw, and the home straight
that never comes. In the corridor
children squeal, drench their hair
with wind. I dangle promises
before myself: the orange glow
of evening; the airborne tang of citrus;
and a strange-tongued aunt ladling Latinate soup,
offering lemons
still warm from the sun.
- Mario Petrucci