"Having Too Much Feather in His Brain"--H.H. Asquith's Remark About Gen. Sir Ian Hamilton

Here is Asquith's comment about Hamilton in a letter to Venetia Stanley (September 30, 1914), from H.H. Asquith, Letters to Venetia Stanley (1982):

Sir Ian Hamilton came to lunch: he commands all the Territorials and is very pleased with a lot of them. Curiously, in England far the best are the North & South Midlands—Stafford, Warwick, Northampton, Derby, Notts &c. Of the Scotch, he puts the Lovat Scouts first. It is strange that the Scottish officers—lairds & sons of lairds &c—are very inferior to the English professional men from the Midlands, solicitors, doctors, architects & such. He is a sanguine enthusiastic person, with a good deal of superficial charm (do you know him?) and much experience of warfare (one of the few survivors of Majuba Hill in 1881) but there is too much feather in his brain.

I don't think the characterization of Hamilton as having "too much feather in his brain" can be read meaningfully without acknowledging the existence of featherbrain as a derogatory term. Merriam-Webster's Eleventh Collegiate Dictionary (2003) gives this information on the term featherbrain:

featherbrain n (1668) : a foolish scatterbrained person.

Interestingly, Webster's New International Dictionary (1909)—published just five years before Asquith's letter to Stanley—has no entry for featherbrain but has this for featherhead:

featherhead n. a A frivolous or light-headed person. "A fool and featherhead." Tennyson. b A weak head. Carlyle.

Back in England, John Ogilvie & Charles Annandale, The Imeperial Dictionary of the English Language (1883) has entries for both both feather-brained and featherhead:

Feather-brained a. Having a weak, empty brain or disposition; frivolous; giddy. To a feather-brained school-girl nothing is sacred. Charlotte Bronte

Featherhead n. A light, giddy, frivolous person; a trifler.'A fool and featherhead.' Tennyson.

One of the more prominent authors to use the term featherbrain in the nineteenth century was Thomas Carlyle, who used it both in The French Revolution: A History (1837):

For long years and generations it [the extreme divide between the wealthy and the impoverished in France] lasted, but the time came. Featherbrain, whom no reasoning and no pleading could touch, the glare of the firebrand had to illuminate: there remained but that method. Consider it, look at it! The widow is gathering nettles for her children's dinner; a perfumed Seigneur, delicately lounging in the Œil-de-Bœuf, has an alchemy whereby he will extract from her the third nettle, and name it Rent and Law: such an arrangement must end.

and in Chartism (1840):

Castle-spectres, in their utmost terror, are but poor mimicries of that real and most real terror which lies in the life of every Man: that, thou coward, is the thing to be afraid of, if thou wilt live in fear. It is but the scratch of a bare bodkin ; it is but the flight of a few days of time ; and even thou, poor palpitating featherbrain, wilt find how real it is. ETERNITY: hast thou heard of that? Is that a fact, or is it no fact? Are Buckingham House and St. Stephens in that, or not in that?

The exact wording "feather in his brain" appears in only one other place in a Google Books search—in the epilogue to John Vanbrugh, The Relapse: or, Virtue in Danger. A comedy (1696):

Far, give me leave t'abserve, good Cloaths are Things/ Have ever been of good Support to Kings;/ All Treasons come from Slovens ; it is nat/ Within the reach of Gentle Beaux to plat;/ They have no Gall; no Spleen, no Teeth, no Stings,/ Of all Gad's Creatures, the most harmless Things./ Thro' all Recard, no Prince was ever slain,/ By one who had a Feather in his Brain./ They're Men of too refin'd an Education,/ To squabble with a Court—for a vile dirty Nation./ I'm very positive you never saw/ A th'ro' Republican a finish'd Beau.

These words, spoken by a character named Lord Foppington, suggest that having a feather in one's brain may involve having an excessive interest in modish appearance. But this instance is of marginal help in understanding Asquith's meaning, partly because Foppington says "a feather in his brain" —not "feather in his brain"—and partly because he said it 218 years before Asquith did.

I see Asquith's remark about Hamilton as criticizing Hamilton for being a lightweight in seriousness and judgment. That, together with Asquith's calling out Hamilton's "superficial charm" leads to a rather damning description of a high-energy but insincere and unreliable person. There may be an implicit accusation of dilettantism at play here, too—as a person today might criticize someone else for having "too much fluff and not enough substance"—but I don't think that the "too much feather in his brain" refers specifically to Hamilton's scholarly accomplishments.