+It will not be performed on outputs whose root elements are
+ `<书社:raw-text>` or `<书社:base64-binary>` (described below).
+
+## Applying Attributes
+
+The `<书社:apply-attributes>` element will apply any attributes on the
+ element to the element(s) it wraps.
+It is especially useful in combination with embeds.
+
+The `<书社:apply-attributes-to-root>` element will apply any attributes
+ on the element to the root node of the final transformation result.
+It is especially useful in combination with output wrapping.
+
+In both cases, attributes from various sources are combined with
+ white·space between them.
+Attribute application takes place after all ordinary transforms have
+ completed.
+
+Both elements ignore attributes in the `xml:` namespace, except for
+ `@xml:lang`, which ignores all but the first definition (including
+ any already present on the root element).
+On H·T·M·L and S·V·G elements, `@lang` has the same behaviour as
+ `@xml:lang`.
+
+## Other Kinds of Output
+
+There are a few special elements in the `书社:` namespace which, if
+ they appear as the toplevel element in a transformation result, cause
+ ⛩️📰 书社 to produce something other than an X·M·L file.
+They are :—
+
+- **`<书社:raw-text>`:**
+ A plaintext (U·T·F‐8) file will be produced from the text nodes in
+ the transformation result.
+
+- **`<书社:base64-binary>`:**
+ The text nodes in the transformation result will, after removing all
+ Ascii whitespace, be treated as a Base·64 string, which is then
+ decoded.