Thursday, December 1, 2022

Remembering a Veteran: Lt. Harry Moseley, 13th Division British Army


Henry G. J. Moseley – Pioneer in Nuclear Physics and the Analytical Use of X-rays, Killed in Action at Suvla Bay,
 Gallipoli,  10 August 1915

By James Patton

Gallipoli Peninsula, June 1915: The Anglo-French invasion was looking like a fiasco. Unwilling to concede failure, Mediterranean Expeditionary Force commander Gen. Sir Ian Hamilton and his staff began to lobby for a new offensive. Churchill supported their cause and Lord Kitchener agreed to contribute three New Army divisions made up of 1914 volunteers now deemed ready for combat. An ambitious, complicated plan was devised, the execution of which would prove to be impossible, and it would be the greatest fiasco within the fiasco. 

The offensive was to begin on 6 August. Diversionary attacks would be launched by the 1st Australian Brigade at Lone Pine and by the British 88th Brigade at Krythia Vineyard in order to hold enemy forces to the south of the real attack zone. Later the 3rd Australian Light Horse Brigade would also launch a diversion at the Nek to draw enemy strength from Chunuk Bair.  




At dawn, the new IX Corps, commanded by Lt. Gen. Sir Frederick Stopford, would land its 11th (Northern) Division at Suvla Bay six miles north of Anzac Cove, with the 10th (Irish) Division to follow on the 7th, the 53rd (Welsh) Division on the 8th and the 54th (East Anglian) Division on the 10th, the latter two being Territorial Army (akin to the U.S. National Guard) units pulled from the defense of the Suez Canal. IX Corps forces were to move inland immediately and push across to the Dardenelles so as to cut off all of the Ottoman forces on the southern end of the peninsula. In order for this ‘push’ to succeed it would be necessary to clear the Sari Bair highlands of Ottoman observation posts.

For this purpose an attack force would be assembled at Anzac consisting of most of the 38th and 39th Brigades of the 13th (Western) Division, the 4th Australian Brigade (commanded by Brig. John Monash, later the commander of all Australian forces on the Western Front), the 1st NZ Infantry Brigade, the NZ Mounted Rifles Brigade and the 29th Indian Brigade, which was an ad hoc force, consisting of three seasoned Gurkha battalions and two New Army battalions detached from the 38th and 39th Brigades. After a forced night march, shortly before dawn on the 7th, a coordinated surprise attack by the Australians, the Gurkhas and the New Zealanders would capture the three high peaks of the Sari Bair Range. These experienced assault troops would be backed up by the green New Army units from the 13th Division.


2nd Lt. Harry Moseley,  RE, 13th Division


This last part was the most intricate part of the plan. For three successive moonless nights about 20,000 men would have to be secretly landed at North Beach (next to Anzac Cove) and somehow hidden from enemy observation and shelling. At dusk on the 6th these units would form into two columns and move out in total darkness. The left column would eventually split and the Australians would capture Hill 971 while the 29th Indian Brigade would capture Hill Q. The right hand column would split much earlier in their march—the NZ Mounted Rifles would clear the enemy from the four low hills of Beauchops, Table Top, Little Table Top and Destroyer, the 1st NZ Brigade would capture Rhododendron Spur and with support from the 38th and 39th Brigades drive the enemy from Chunuk Bair. Incredibly, all of this was to happen by noon the next day.

Problems were immediately apparent and just kept on coming. There was nowhere near enough space at North Beach to accommodate the Sari Bair attack force, with the result that the element of surprise was lost and also that the sequence of advance was greatly scrambled. There was no moonlight, the terrain was rough and rocky, maps were poor at best and wrong at worst, and there were no guides. Soldiers and mule trains were asked to advance through uneven, narrow, winding, partly blocked defiles less than one yard in width with cliffs on each side rising as much as 600 feet. In desperation, some units tried to find short-cuts, which slowed them down even more, left them in the wrong place and increased the confusion. Even the highly regarded Australians and Gurkhas couldn’t advance fast enough to meet the ridiculous timetable; they had also been given the longest marches. The order of battle broke down as the inexperienced New Army units were lost, confused and exhausted, and the result was a fiasco, a jumble of ad hoc forces.  

The low hills were cleared but several hours behind schedule and at zero hour on the 7th no assault unit was fully in place. The 1st NZ Brigade, short two battalions still on the way, did launch an attack on Chunuk Bair in the afternoon, which was repulsed with heavy casualties, and served to fully alert the enemy. Later that night, an ad hoc force of a battalion from the 1st NZ plus two battalions from the 13th Division succeeded in capturing part of the summit of the peak. This was to be the high point of the August Offensive. The Gurkhas didn’t get their ad hoc force organized for an assault on Hill Q until the morning of the 10th, and heroically captured the top only to lose it to a fiasco; they were shelled by the Royal Navy ships offshore. The Australians never made it as far as Hill 971. 

Meanwhile, unbelievable events were happening up at Suvla Bay. Stopford had decided to consolidate his forces on the beach before moving to cut the peninsula. While men were fighting and dying on the Sari Bair ridges and in the diversions, Stopford’s men were pitching camp. He had simply decided not to proceed until the 9th, when he would have three divisions. By the time the IX Corps attack began, the Ottomans had moved in massive reinforcements and by nightfall on the 9th IX Corps had been stopped cold short of the Tekke Tepe Ridge. It would get no farther. 

Another fiasco; Stopford was in no way up to the task given him. His career had been spent in staff positions and home commands, and he had retired in 1909. One critic said of him that he had "no conception of what generalship meant." Kitchener had appointed him to IX Corps simply because he was the only Lt. General on the list without a command, over Gen. Hamilton’s strenuous objections.   

"The Farm" in the Foreground, Where Moseley Would Fall


Meanwhile, back at the peaks several units from the New Army brigades had congregated at the head of a ravine called Chailik Dere. Those detached from the left hand assault column had been delayed in getting to Rhododendron Spur and while they waited they were joined by others from the right column. This randomly created ad hoc force became known as Baldwin’s Brigade, as the senior officer on site was the commander of the 38th Brigade, Brig. A.H. Baldwin, but it contained soldiers from all three brigades of the 13th Division and mostly not from the 38th. On the 9th this force was ordered to attack the north side of Chunuk Bair and the south end of Hill Q, but due to disorganization only managed to get as far as the low flat-topped hill directly below the peaks called "The Farm" (See map and photo above). There Baldwin had to detach two battalions to relieve the NZ Mounted Rifles still holding out up on the summit of Chunuk Bair.

Fiasco struck again. On the 10th the stalled offensive against the peaks collapsed. Four regiments of Ottoman troops had been shifted from the Helles Front, and at dawn they counterattacked. Personally led by Col. Mustafa Kemal, 30,000 soldiers charged up the reverse slope of Chunuk Bair, sweeping aside the defending 6th Loyal N Lancs (38th Brigade), and 5th Wilts (40th Brigade), the men that Baldwin had sent up as relief. Kemal’s men then poured down the steep incline to The Farm and smashed into Baldwin’s hapless, bone-weary men, who had not constructed defensive positions. An observer at the Apex position at the base of Rhododendron Spur likened the sight to a “human waterfall.” Baldwin and his entire command post were wiped out, including the 38th Brigade’s signals officer, 27 year old Royal Engineer 2nd Lt. Henry Gwyn Jeffreys Moseley, the most promising English physicist of his generation.


Moseley's Body Was Never Recovered; He Is Listed on
the Helles Memorial, Gallipoli Peninsula


Moseley, familiarly called "Harry," was born into a wealthy, eccentric, scientific family in 1887. His grandfather was the Rev. Canon Henry Moseley, who was also a hydrologist and naval architect, his father was Henry N. Moseley (1844–91), a comparative anatomist and member of the Challenger Expedition (1872-6) who became the second Linacre Professor of Zoology at Oxford (1881–91), and his maternal grandfather John Gwyn Jeffreys (1809–85) was a very successful Welsh solicitor who was passionately interested in mollusks and a member of the Royal Society. Predictably, Harry was encouraged by his mother to study natural sciences, but was led into physical sciences instead. He attended Eton and then went up to Trinity College, Oxford. In his time Oxford was dominated by classical dons and wasn’t a beehive for scientific education or research. In 1909 Harry completed the Officer Training Course, a portentous event. He graduated in 1910 with a Second; to that point Oxford had only awarded one First in physics. 

Harry’s ambition was to go to work at the Victoria University of Manchester, under the great Nobel Laureate Sir Ernest Rutherford. Surprisingly, his application was accepted. Harry wrote to Rutherford: “It will be my great pleasure to work in your laboratory, and after my failure in ‘schools’ I consider myself very lucky to have got the opening which I coveted.” That Harry had a living courtesy of his grandfathers may well have tipped the scales in his favor, but Rutherford would never for a moment regret his choice.

When Harry arrived in the fall of 1910, Rutherford’s laboratory was teeming with groundbreaking discoveries about atomic structure. Since the discovery of the electron in 1897 by Rutherford’s mentor and Nobel Laureate Sir J.J. Thomson at Cambridge, many were working to find all of the sub-atomic particles and learn how they fit together. Two members of Rutherford’s laboratory, Ernest Marsden and Hans Geiger, had been trying to answer this question by bombarding ultra-thin sheets of gold foil with alpha particles, the positively charged particles that Rutherford had found in the decay of radium. Most of the time, the alpha particles would pass through the gold foil, but occasionally one bounced almost straight back. Rutherford later wrote of this experiment “it was the most incredible thing that has ever happened to me. It was almost as if you had fired a 15-inch shell at a piece of tissue paper and it came back and hit you!”

As a result of this research, Rutherford postulated his atomic theory: all of the positive charge and most of the mass of the atom were concentrated in a tiny central core with the electrons orbiting this "nucleus," and most of the atom was empty space. Historian David Kaiser has written “today we take this picture that Rutherford put together for granted, but it was really pretty new in its day. I think the feeling in those hallways, the laboratories of Manchester, must have been one of great excitement. They could sense that Rutherford and his team had literally cracked open a new view of matter.”

 

In 1912 the University of Manchester physics laboratory headed by Ernest Rutherford (second row center) included Harry Moseley (bottom second from left), Hans Geiger (inventor of the Geiger counter), Charles G. Darwin (grandson of the great biologist) and James Chadwick, who would later win the Nobel Prize for discovering the neutron.


Meanwhile, the newcomer Harry Moseley wasn’t involved in these experiments. He was attempting to replicate the findings of others and, on the side working on Rutherford’s idea of an atomic battery, an idea that would be perfected in the 1950s. In 1912 the Royal Society published Harry’s first paper, on properties of Beta Rays, but when delivery of a piece of equipment was delayed, he used his down time to find a new direction for his research. Learning of the recent German discovery that X-rays could be "diffracted" in much the way light can be broken into a spectrum of colors with different frequencies, Harry teamed with Charles G. Darwin (grandson of the great biologist Charles R. Darwin), and they refined the German results to the extent that the clarity of the spectra allowed atomic structure to become the subject of the experiment, rather than X-rays.

Carrying on without Darwin, Harry then discovered that each element has a unique X-ray diffraction spectrum—like a fingerprint that can identify that element. More surprising, he found a simple relationship between an element’s spectrum and its "atomic number."

Niels Bohr’s theory suggested that it would be atomic number that the X-ray spectra corresponded to, as their energy depended on the outermost electron and the nature of this electron depended on the atomic number. Harry’s research provided the solution. He postulated a theory (later called Moseley’s law) which proved what Bohr had suspected – that the frequency of X-rays is proportional to the atomic charge. The elements could be ordered according to atomic number. Up to then, atomic number had just referred to the number of an element’s box in the Periodic Table. Harry’s work showed it was actually a measure of the positive charge on an atom’s nucleus. In November he published his famous step ladder, showing the increasing frequency of the X-rays from calcium to copper. 

 

Moseley's First Step Chart 


Building on Harry’s work, Rutherford would soon discover the subatomic particle responsible for this charge—the proton. These discoveries put the Periodic Table in a whole new light. Its author, Dmitri Mendeleev, had relied on atomic weight in building the table, but Moseley and Rutherford showed the table’s foundation is actually atomic number: Each element in the table has one more proton in its nucleus than the element before it. 

Incredibly, just by using his X-ray spectroscope, Harry could quickly determine whether a sample contained a new element or was a compound of known elements. “He could distinguish between types of matter, with a brand new technique, not dependent on their chemical properties, but by measuring their atomic numbers based on these X-rays,” Kaiser says.

Harry was able to solve Mendeleev's problem of the “rare earths,” certain elements whose properties were so similar that they had confounded chemists. “Moseley, who couldn’t tell one rare earth from another, had this wonderful machine that could tell whether or not the specimen in question had the right credentials to be a new element,” says biographer John Heilbron.

And perhaps his most electrifying finding: Harry could tell exactly how many elements remained to be discovered —and where they would fall in the Periodic Table. “The idea that somebody could know how many elements God created—that was terrific,” Heilbron says.

In a few short years Harry had set forth the basis for the modern periodic table, predicted the elements that would fill in the gaps and showed that x-rays could be a supreme analytical tool. Few achieve in a lifetime of research what he achieved in a career of just 40 months.

Joseph Nordgren of Uppsala University in Sweden thinks Harry could have counted on a Nobel Prize. He was actually a nominee for the 1914 prize for Physics. It is also striking that no prize for Physics was awarded for 1916.  Strangely, Nordgren says, the 1924 prize for Physics was awarded to Manne Siegbahn, who didn’t make a tangible discovery. “Siegbahn’s improvements made other discoveries possible. But if you want to find a distinct discovery … it’s very hard.” This was discussed by the committee of 1924, before they eventually awarded Siegbahn the prize anyway. His improvements, impressive as they were, were built on the work of Moseley. Nordgren contends that Siegbahn got Harry’s Nobel. 


Commemorative Plaque, Oxford University

Harry was tragically unlucky in that he came of age in an era when war was considered an adventure rather than a catastrophe. Rutherford later wrote in a newspaper article: “It is a national tragedy that our military organization at the start was so inelastic as to be unable, with a few exceptions, to utilize the offers of services of our scientific men except as combatants in the firing line. Our regret for the untimely death of Moseley is all the more poignant because we recognize that his services would have been far more useful to his country in one of the numerous fields of scientific inquiry rendered necessary by the war than by the exposure to the chances of a Turkish bullet.” 

For more please see:

Heilbron, J.L.  The Life and Letters of an English Physicist 1887-1915 University of California Press, Berkeley and Los Angeles: 1974. The definitive work about Moseley, although some parts are difficult reading for non-physicists.


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