Kaoru Mori's art in volume 1 of Emma (booklog) is so unobtrusive but so charming that I had the terrible urge to take it appear and see how it worked. I can't pretend to have found anything startling, but a few naive comments (and spoilers, though as they're only for volume 1, they aren't really serious) are behind the cut.
Images are from scanlations by the iichan group. Click on an image for a larger version (except the ones that are marked up). Reference format: volume-chapter-page (by published version's numbering).
And as-you-know-Bob, manga is read from right to left.
Generally speaking, the art tends towards either realism, in the backgrounds, or the appearance of realism, in the characters—which is to say that I know intellectually that people's faces don't look like that, but the way they're drawn doesn't make me think "cartoon!" (This may be a genre difference, as well; I've seen Emma referred to both josei and seinen, (roughly) adult men and adult women's manga, which surprises me a bit because the same story in the U.S. would almost certainly be shelved under romance.) Because of this, there's not a lot of obvious or obtrusive art effects to talk about; but once I started looking at the art with an analytic eye, I found a few things.
Since page structure is one of my hobbyhorses, I'll start with that. The panels in this volume are almost always rectangular. The first difference is on 1-01-013:
I found this remarkably effective at disrupting my reading, emphasizing William's surprised pause. (And while this isn't particularly unusual, it's a good selective use of backgrounds.)
I was interested that a very similar diagonal had exactly the opposite effect just a few pages later, on 1-01-018:
There, the effect was to speed things up, emphasizing William's being shown the door: the angle's within a panel, not between them, and is defined by content rather than white space, thusly:
Though the panels are usually very regular and rectangular, their pages do sometimes have an overall layout that echoes their theme or actions. I first noticed this on 1-01-011:
This has a nice clockwise curve arrangement, but more than that, the structure emphasizes how Mrs. Stowner's presence diminishes William:
The above layout works well with the standard reading order, but toward the end of the volume the overall page shape and the reading order conflict with each other, at 1-07-180:
At first glance, this also looks like a clockwise curve around a burst of white space, thusly:
But the actual reading order is much less intuitive:
I think the page (and maybe the surrounding pages too) would have to be completely restructured to avoid this problem, but it did trip me up on the first reading as I tried to follow the art, rather than the usual right-left order.
Then there are page layouts that are independent of reading order, just expressing a theme when the page is viewed as a whole. I particularly like the three pages starting with 1-01-024:
Emma and William start out apart, and then meet up. Not only are they in separate panels in 1-01-024, but their figures form a triangle that widens as one reads down the page. On the next page, as they get closer and closer, their figures describe a triangle again, but one that narrows. Then, on the page after that:
This page is also set up as a narrowing triangle, to show that they come together emotionally after doing so physically, through an invitation and a decision. And then the bottom panel has a road as a background rather than a building, emphasizing their decision to walk together.
(Aren't they cute? I love the body language. Who needs words?)
There's a similar effect next chapter, on 1-02-049, but this time the page structure is an X, emphasizing their difference of opinion as Emma declines William's offer to buy her new glasses:
Very simple, very effective. I like the way the pages make use of blocks of dark and light (William's usual garb is handy for this).
A page where I thought there was insufficient contrast is on 1-03-060:
William stands out very well, a little outraged patch of simple black among a whole lot of light-colored stuff; but I didn't realize that the last two panels had a focal point until the person below the umbrella was revealed on the next page. (I barely realized there was an umbrella.) Unfortunately I don't think there would have been a way to do it differently and still have the same effect, but I found it confusing.
Also speaking of lights and darks, this page (1-02-038) has a very rare use of tones, a fittingly simple gray:
There's so much black and white on the page already that the plain gray tone works best to just pause and show Emma's shock. (I also like the way the dark elements of the three last panels draw the eye down the page.)
And that's about all I have on volume 1 of Emma. Have comments of your own? (If you do, but don't have scans, give me the page number and I will upload it for discussion.)