Heading out of town for Labor Day weekend? Take a tip from local restaurateur Ellen Kassoff Gray, who has mastered the art of feeding her family en route with the help of ingredients bought at farmers markets. You can pick up her tips and tricks in today’s Food section.

Also today, Sourced columnist David Hagedorn tells us why he chooses pastured chickens for his kitchen; and read all about a mill owner’s attempts to re-create the kind of flour that was ground hundreds of years ago.

And finally, don’t forget to join us at noon for the Free Range chat, our weekly hour of culinary give-and-take. Bring your questions, and we’ll answer them. And if we can’t get to yours, maybe we can field it in this space next week. Like this question from a previous chat:

When measuring ingredients the other day, for some reasons I decided to transfer the sugar from the measuring cup to the larger Pyrex measurer and was shocked to find that what had been one full cup was less than that in the larger container. So I repeated the experiment with the other ingredients (flour, butter) and got the same result: I had to add maybe two tablespoons more per cup, to meet the Pyrex lines. Should I automatically trust the Pyrex and assume the measuring cups — manufacturer’s name long since gone, but purchased at a kitchen store — are wrong? Or is it just as likely that the Pyrex is off? I don’t have a kitchen scale so can’t use that as an independent arbiter.

There might be nothing wrong with any of your measuring gear. Though it’s true that a cup is a cup is a cup, you can still get different results measuring the same ingredient in the two different kinds of cups. That’s why you’re always supposed to measure dry ingredients in dry measuring cups and liquid ingredients in liquid measurers.

I’ll let Cook’s Illustrated explain why: “Although liquid and dry measuring cups hold the same volume, in a liquid measuring cup, there is no way to level the surface of the contents to obtain an exact measurement.” So imagine that you’ve poured your sugar into the liquid measurer, and you need to level it off to see how much you have. The more you wiggle, jiggle or shake the container to level the sugar, the more you compact it and throw off the measurement.

What’s more, according to the educational Web site Infoplease, “solids pack more tightly when they’re given a wider space in which to spread out. Liquid measuring cups are usually wider than solid measuring cups.”

When you measure a dry ingredient in the correct kind of cup, you achieve accuracy by sweeping a straight edge across the top. But when you pour a liquid into a dry cup, it’s hard to get it exactly even with the rim without spilling. You need a clear glass or plastic vessel, read at eye level, for an accurate measurement (unless you have one of the newer read-from-above glass cups).

Now, on the other hand, there’s no official bureau or agency governing standards for kitchen measuring equipment. (I have a beautiful set of pounded pewter measuring spoons that is so wildly off, it is basically just a decorative wall hanging now.) You can do a simple experiment by measuring out 16 tablespoons of sugar (leveling the top each time with a straight edge) and seeing how well that fits into your dry-measure cup. Of course, without a kitchen scale you have no way of knowing whether your tablespoon measure is accurate, either! But if your results are way off, that would tell you that there’s a problem somewhere.

None of this would be an issue if we’d measure recipe ingredients by weight. SO much more accurate and consistent. But although that’s the way it works in many other countries, we do seem to love our cups here in the USA, so I’m not seeing that happening any time soon. I do see more recipes offering helpful weight info these days, though. (And we try to do that in our Washington Post recipes when it’s important.)

p.s. You DO need a kitchen scale. Go get one, and you’ll wonder how you ever got by without it. And you’ll be able to test whether your Pyrex cup actually holds 236 grams of water!