BOO BOO SALVE

The history: Olive oil is the oldest carrier in the western world, pressed for lamps, for cooking, and for every ointment in every old pharmacopoeia.

Traditional use: One ounce each of the three dried herbs to a quart jar, covered in olive oil and steeped, then set with beeswax. This is the kitchen-counter salve of the family.

The science: Olive oil is high in oleic acid and rests on the skin as a soft, breathable film, which makes it a willing carrier for dried herb infusions and wax. It is 92 percent of this tin.

The history: A North American native, called Oswego tea by the Haudenosaunee and brewed as a leaf tea long before it became a garden flower.

Traditional use: The leaf, dried and steeped in oil, worked into salves for weathered skin, and planted at the edge of the garden where the bees find it.

The science: Its leaves carry thymol and other aromatic compounds, which is why this infusion smells bright and green. Ours is grown here, dried here, and used at one ounce per quart.

The history: Achilles' herb. Legend says the warrior carried yarrow into battle, and it has been the meadow's first-aid plant ever since.

Traditional use: The feathered flower head dried and steeped in oil, one of the oldest topical herbs in European and North American folk practice.

The science: Yarrow brings the bitter, camphor-green note to the infusion, and it belongs to the Asteraceae family, which matters if you carry a daisy allergy.

The history: Old herbalists called it knitbone, and the name appears in European herbals going back a thousand years.

Traditional use: The dried leaf steeped in oil as the standard cottage-garden salve herb, always for external use.

The science: Comfrey leaf is rich in allantoin and rosmarinic acid. It belongs in a spot salve, worked into one rough patch, rather than in something you sweep over your whole body.

The history: The oldest cosmetic wax we know of, used to set ointments in Egypt and Rome.

Traditional use: The set and the seal, so the oil stays exactly where you put it.

The science: Its long-chain esters form a breathable, water-resistant film over the spot you are treating, which is why one thin layer lasts through a hand wash.

The history: Identified in wheat germ oil in 1922 and named from the Greek for bearing, for the role it plays in the body.

Traditional use: The salve maker's insurance, added to keep a natural oil from turning before its time.

The science: A fat-soluble antioxidant that slows oxidation in the olive infusion so the tin stays good to the last swipe.

The history: The same three oils the original family tin carried, unchanged, because the smell is half the reason anyone reaches for it.

Traditional use: Lavender to calm, tea tree for the clean sharp note, distilled lemon for a bright finish on the dry-down.

The science: Together they sit at about 1.5 percent of the tin, a gentle family-strength level. The lemon is steam distilled only, because cold-pressed lemon peel is phototoxic in a leave-on product.