An inconvenient gas

Lord Rayleigh was working on the definitive density of nitrogen when he found a difference in the density of nitrogen prepared from the atmosphere and that prepared from various compounds. He was so perplexed that he wrote to Nature seeking advice from the readers. Ramsay and Crookes became interested in the problem.
Rayleigh undertook a literature search. Again Rayleigh had difficulties. The only definitive work in the field was over 100 years old and was written in "terms of the phlogiston theory". No doubt, Rayleigh took a deep breath and prepared to do some interpreting as scientific terms and theories change over time.

Here is Cavendish’s summary
" …if there is any part of the dephlogisticated air of our atmosphere which differs from the rest and cannot be reduced to nitrous acid, we may safely conclude that it is not more than 1/120 part of the whole."

Rayleigh became fascinated. He repeated Cavendish’s experiments. He investigated the gas so formed. Ramsay, Crookes and even James Dewar were also interested in the gas. Finally Rayleigh and Ramsay announced the discovery of argon to the Royal Society on 31 January 1895. Spectroscopic evidence was an important tool in the later period of investigation.

Dewar and others would not concede the possibility of a monatomic gas.
Rayleigh, a physicist, was unwilling to change his findings to fit argon into the "Periodic Table".
The "Table" was empirically not mathematically based.
Rayleigh returned to physics "where second rate men seem to know their place".

What happened to "young Marsden"?
Ernest Marsden was in his honours year when Hans Geiger, his supervisor, approached the Prof (Rutherford) for a suitable project.
Marsden ended up working on the gold leaf / alpha particle project.
After graduating, Marsden went to London but soon returned to Manchester to continue work with Geiger and Rutherford.
There is supposed to be a Chinese curse "May you live in exciting times".
Marsden lived in exciting times. He helped form the modern concept of the atom.

What did happen to "young Marsden"?
I asked John Packer (Emeritus Professor of Chemistry, University of Auckland). Here is his reply.

Dear Bernard,
"Young Marsden" first held the chair of physics at Victoria University of Wellington (I think this is correct) and then became head of our DSIR, our equivalent to your CSIRO (but no longer in existence). After he retired from that he was NZ science liaison officer in London for a while, because I met him in that capacity when I first went to London as a member of the NZ Defence Science Corps to do my PhD. I tried ringing our physics nuclear man but did not get an answer. I shall try again later and if I find the above information is incorrect I shall let you know. I have never heard of Jim Stephenson, but I shall make inquiries. Unfortunately the people who would best know are dying off or dead!
Best wishes,
John