Topping off "McDowell's obnoxious hat"

I read John Hennessy and I forgot. Harry Smeltzer read and remembered. Harry:
Return to Bull Run, pp 7-8: "Some men even questioned McDowell’s loyalty, suggesting that the prominent hat he wore, 'which looked like an esquimaux canoe on his head, wrong side up,' served as a covert signal to the enemy that he was present and 'all was well.'" The footnote reads "for debate over McDowell’s obnoxious hat see the National Tribune, issues of November 12, 1891, March 31, 1892 and April 14, 1892."
His obnoxious hat! An Eskimo kayak! Tim Reese adds:
I have to agree with Harry. This is no proof that McD's helmet ever had a spike. Still, the allusion to "white" draws aside the veil of doubt somewhat. As before conjectured, he [McDowell] probably acquired one of the generic types pictured at top center of my montage. These were more often described as a coal scuttle turned upside down, rather than a canoe. Their white canvas was usually dyed with tea to deaden the glare, faint concession to camouflage.
When was Averell writing; postwar I presume after the spiked, white cork helmet had come into US service, however briefly. I'll wager that McD's had a pugri, a folded cloth wound about the base w/curtain (Havelock) at rear, this to deflect/absorb saber blows...

As an amusing aside, it was customary and traditional for British troops returning from the East to cast their battered toppees overboard when reaching the western terminus of the Suez Canal near Port Said. East meets West, so to speak. Ah, back to civilized head dress.
Postscript added 9/14/06 after Harry dug up Averell's unfinished memoir. Harry writes:
The manuscript of Averell’s memoirs (Ten Years in the Saddle) was begun in 1891, and was unfinished at the general’s death in 1900. On page 289 he describes McDowell’s appearance on the morning of 7/16/61, as his army began its movement on Manassas Junction:

"The scene presented on the gran portico of Arlington House on that day when McDowell came forth arrayed for the field in the uniform of a Brigadier General and otherwise distinguished by his white helmet with the bright lance-head on top, and followed by a well appointed staff, was impressive."

Anything is possible: McD may have had a lance head on the helmet, perhaps even custom fit it himself; Averell, writing in old age, may have mis-remembered, and morphed McD’s helmet with those that became popular in the intervening years; or Averell may have added the spike for dramatic effect - the polished spike representing the high hopes of the man and the nation as the campaign kicked off, the broken lance-head at the exhausted McD’s feet symbolic of the broken man and the broken dreams of a quick end to the war.
Many thanks to Harry and Tim for their input on this.