A single page from R. Penn's lab notebook, marbled boards, ruled grid, 1957 volume. Page 142. Reproduced here in its original layout — entries in blue ink; columns in pencil; one revision in red pencil; one further note in a different black ink.
Page 142. R. Penn — beet anthocyanin chromatography — series 17 / continued from p. 140.
Date of run: 18 September 1957. Column packed 16 Sept (silica, J. T. Baker lot 7714).
Solvent system: 4:1 chloroform : methanol (v/v), as in series 16 except —
FRACTION · TIME · ABSORBANCE (520 nm) · pH · NOTE
- 1 · 04:30 · 0.142 · 4.20 · pale, near baseline
- 2 · 09:00 · 0.221 · 4.20 · slight rise
- 3 · 13:30 · 0.418 · 4.20 · red shoulder onset
- 4 · 18:00 · 0.821 · 4.20 · band centred
- 5 · 22:30 · 0.418 · 4.20 · trailing
- 6 · 27:00 · 0.221 · 4.20 · ~ to fraction 2
- 7 · 31:30 · 0.142 · 4.20 · ~ to fraction 1
Below the table, in Penn's hand:
Band centre at 18:00 (fraction 4). Width ~9 minutes from half-rise to half-fall, symmetric. The shoulder structure is the same on every column I have run since June. I am going to call this band, conservatively, Penn's red-orange, an anthocyanin congener of unusual symmetry; further work to elucidate the precise structure is for the thesis chapter on β-elimination products. — R.P., 18.ix.57.
Pencil annotation, in Penn's hand, slightly later:
Series 16 had the same retention time and the same pH-invariance and an identical absorbance profile. The two series differ only in column-packing date. The reproducibility is unusual; I am noting it for the thesis. — R.P.
Red pencil, undated, in a hand that is also Penn's but in a different pencil:
Galt's column trials, if she is to be believed, give a band of identical retention time and identical pH-invariance in carrot extract. I do not believe she is to be believed. Tomorrow I will show her where her arithmetic loses a decimal. — R.P.
Below the red pencil, in a much later black ink, undated, with a different pen-stroke pressure than any prior entry on the page:
I have not yet shown her. — R.P.