The late Bruce Olsen, a frequent early contributor and a great researcher commented on this is his "Scarce Songs 2" file in his website which is preserved as "Bruce Olsen's Website"

http://www.csufresno.edu/folklore/Olson/SONGTXT2.HTM#BRAESBAL

at the University of California at Fresno. Some of what I paste here refers to another page on his site that contains tunes.

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How do we get from the first tune below to Francis McPeake's
"Will you go lassie go"? Evolution.

First tune, 1740. No verses of that date known:
Play S2: BRAESBAL1- Braes o' Balquhidder

Dance "Braes o' Balquhidder", to the 1740 calls as follows:

FIRST Couple Right hands across with 2nd Couple quite round and
cast off 2nd Couple's place. first Couple right hands across with
3rd Couple and cast off quite round, and cast off below them.
Lead up to the left, and cast off; down thire[?] the 3rd Couple,
and cast up. SETT across & turn. Lead out at the sides, & turn in
the middle.

Here's what Jack Campin discovered in a rare book of 1796, song
and tune:

The Braes o' Bowhether.

Now the day's growin' lang lass,
an' sweet shines the weather,
an' we'll owre a' the hills,
to the Braes o' Bowhether.
Amang the Glens an' Rashy dens,
I'll prize thee without measure,
Within my arms, wi' a' thy charms,
I'll clasp my lovely treasure,
In sweetest Love, our time will move,
wi' mair than earthly pleasure;
By the little limpid streams,
On the Braes o' Bowhether.

An' I'll ay loe thee dearly,
Ilk day wes' forgather,
Syne we'll row on the fog,
By the Braes o' Bowhether;
To Pipe or Flute, when time will suit,
We'll dance like ony feather,
An', skip the knowes where Claver grows,
or stray amang the Heather;
Ay free frae strife in sic a life,
There, weary shall we never,
By the limpid little streams,
On the Braes o' Bowhether.

Play S2:BRAESBAL2- The Braes o' Bowhether
    S2:BRAESBAL4- Braes o' Balquhidder

Robert Tannahil seems to have known a bit of the old song, but he
either didn't know, or didn't like it's tune. From Graham's
'Songs of Scotland' we get Robert Tannahill's "The Braes of
Balquhidder"

Will you go lassie, go,
To the Braes o' Balquhidder?
Where the blaeberries grow,
'Mang the bonnie bloomin' heather;
Where the deer and the rae,
Lightly bounding together,
Sport the lang summer day
'Mang the braes o' Balquhidder,
[Cho:] Will you go lassie go,
To the braes o' Balquhidder?
Where the blaeberries grow,
'Mang the bonnie bloomin' heather.

I will twine thee a bower
By the clear siller fountain,
An' I'll cover it o'er
Wi' the flowers o' the mountain:
I will range through the wilds,
An' the deep glens sae dreary,
An' return wi' their spoils
To the bower o' my deary.
Will ye go, &c.

When the rude winty win'
Idly raves round our dwellin',
An' the roar o' the linn
On the night breeze is swellin',
Sae merrily we'll sing,
As the storm rattles o'er us,
Till the dear sheeling ring
Wi' the light liltin' chorus.
Will ye go, &c.

Now the summer time is in prime,
Wi' the flowers richly bloomin',
An' the wild mountain thyme
A' the moorlands perfumin',
To our dear native scenes
Let us journey together,
Where glad innocence reigns
'Mang the braes o' Balquhidder.
Will ye go, &c.

Graham said the tune was in Capt. Fraser's 'Highland Melodies',
1816, #77, with slight differenes from that (later) in R. A.
Smith's 'Scottish Minstrel' I, p. 49 (I don't have).

Capt. Fraser's heading to the tune is:

Bochuidear      Balquhidder. As performed by Major Logan

Play S2: BRAESBAL3-Bochuidear...Balquhidder.



WILD MOUNTAIN THYME
(Jimmy McPeake)
1. Oh, the summer time is coming,
   And the trees are sweetly blooming,
   And the wild mountain thyme
   grows around the blooming heather.
[Cho: Will you go, lassie, go?
   And we'll all go together
   To pull wild mountain thyme
   All around the blooming heather,
   Will you go lassie, go?

2. I will build my love a bower
   By yon clear and crystal fountain,
   And on it I will pile
   All the flowers of the mountain.

3. If my true love, she won't have me,
   I will surely find another
   To pull wild mountain thyme
   All around the blooming heather.

4. Oh, the summer time is coming
   And the trees are sweetly blooming
   And the wild mountain thyme
   Grows around the blooming heather.

Transcribed by Sondra Stigen
[End Quotation]

It adds a bit and Olsen's references are almost invariably accurate.