SS Great Britain is a museum ship and former passenger steamship, advanced for her time. She was the longest passenger ship in the world from 1845 to 1854, she was designed by Isambard Kingdom Brunel, for the Great Western Steamship Company's transatlantic service between Bristol and New York. While other ships had been built of iron or equipped with a screw propeller, Great Britain was the first to combine these features in a large ocean-going ship, she was the first iron steamer to cross the Atlantic, which she did in the time of 14 days. The ship has a 3,400-ton displacement, she was powered by two inclined 2 cylinder engines of the direct-acting type, with twin high pressure cylinders and twin low pressure cylinders 88 in bore, all of 6-foot stroke cylinders. She was provided with secondary masts for sail power; the four decks provided accommodation for a crew of 120, plus 360 passengers who were provided with cabins, dining and promenade saloons. When launched in 1843, Great Britain was by far the largest vessel afloat.

But her protracted construction time of six years and high cost had left her owners in a difficult financial position, they were forced out of business in 1846, having spent all their remaining funds refloating the ship after she ran aground at Dundrum Bay in County Down near Newcastle in what is now Northern Ireland, after a navigation error. In 1852 she was repaired. Great Britain carried thousands of immigrants to Australia from 1852 until being converted to all-sail in 1881. Three years she was retired to the Falkland Islands, where she was used as a warehouse, quarantine ship and coal hulk until she was scuttled and sunk in 1937, 98 years since being laid down at the start of her construction. In 1970, after Great Britain had lain under water and abandoned for 33 years, Sir Jack Arnold Hayward, OBE paid for the vessel to be raised and repaired enough to be towed north through the Atlantic back to the United Kingdom, returned to the Bristol dry dock where she had been built 127 years earlier.

Hayward was a prominent businessman, developer and owner of the English football club Wolverhampton Wanderers. Now listed as part of the National Historic Fleet, Great Britain is a visitor attraction and museum ship in Bristol Harbour, with between 150,000 and 200,000 visitors annually. After the initial success of its first liner, SS Great Western of 1838, the Great Western Steamship Company collected materials for a sister ship, tentatively named City of New York; the same engineering team that had collaborated so on Great Western—Isambard Brunel, Thomas Guppy, Christopher Claxton and William Patterson—was again assembled. This time however, whose reputation was at its height, came to assert overall control over design of the ship—a state of affairs that would have far-reaching consequences for the company. Construction was carried out in a specially adapted dry dock in England. Two chance encounters were to profoundly affect the design of Great Britain. In late 1838, John Laird's 213-foot English Channel packet ship Rainbow—the largest iron-hulled ship in service—made a stop at Bristol.

Brunel despatched his associates Christopher Claxton and William Patterson to make a return voyage to Antwerp on Rainbow to assess the utility of the new building material. Both men returned as converts to iron-hulled technology, Brunel scrapped his plans to build a wooden ship and persuaded the company directors to build an iron-hulled ship. Great Britain's builders recognised a number of advantages of iron over the traditional wooden hull. Wood was becoming more expensive. Iron hulls were not subject to dry rot or woodworm, they were lighter in weight and less bulky; the chief advantage of the iron hull was its much greater structural strength. The practical limit on the length of a wooden-hulled ship is about 300 feet, after which hogging—the flexing of the hull as waves pass beneath it—becomes too great. Iron hulls are far less subject to hogging, so that the potential size of an iron-hulled ship is much greater; the ship's designers, led by Brunel, were cautious in the adaptation of their plans to iron hulled-technology.

With each successive draft however, the ship grew larger and bolder in conception. By the fifth draft, the vessel had grown to 3,400 tons, over 1,000 tons larger than any ship in existence. In early 1840, a second chance encounter occurred, the arrival of the revolutionary SS Archimedes at Bristol, the first screw-propelled steamship, completed only a few months before by F. P. Smith's Propeller Steamship Company. Brunel had been looking into methods of improving the performance of Great Britain's paddlewheels, took an immediate interest in the new technology. Smith, sensing a prestigious new customer for his own company, agreed to lend Archimedes to Brunel for extended tests. Over several months and Brunel tested a number of different propellers on Archimedes to find the most efficient design, a four-bladed model submitted by Smith. Having satisfied himself as to the advantages of screw propulsion, Brunel wrote to the company directors to persuade them to embark on a second major design change, abandoning the paddlewheel engines—already half constructed—for new engines suitable for powering a propeller.

Brunel listed the advantages of the screw propeller over the paddlewheel as follows: Screw propulsion machinery was lighter in weight, thus improving fuel economy.

Dr Pearl Dunlevy, was an Irish physician and epidemiologist working on TB and was the first woman president of the Biological Society of the Royal College of Surgeons of Ireland. Born to George Dunlevy and Maggie Doherty, in Mountcharles, Co. Donegal, Bridget Margaret Mary Dunlevy, known as Pearl, was one of six children, she had four brothers and a sister. She was educated in the Loreto Convent, St Stephen's Green, Dublin well as St. Louis Convent in Carrickmacross, Co. Monaghan. Dunlevy studied medicine at the Royal College of Surgeons in Ireland and graduated in 1932 coming first in the exams, she was a student of Sir Thomas Myles. Moving to the UK Dunlevy worked in a number of British hospitals: 1932–1933 House physician, Eye Hospital, Newcastle-upon-Tyne 1933 House physician and surgeon, Nuneaton General Hospital 1933-1934 Resident surgical officer, Birmingham Children's Hospital 1934 Medical officer, Sydenham Children's Hospital, London 1934–1935 House surgeon, Standon Hall Orthopaedic Hospital, Staffordshire.

Returning to Ireland in 1936 Dunlevy graduated in first place from University College Dublin with a diploma in public health and was appointed temporary assistant county medical officer of health in Donegal. After two years she was appointed assistant medical officer of health in Dublin. While in Dublin Dunlevy was resident at Crooksling tuberculosis sanatorium where she gained substantial experience in the treatment and control of childhood Tuberculosis cases. In 1945 Dunlevy established the Primary TB clinic in Dublin at the Carnegie Trust Child Welfare Centre in Lord Edward Street; the aim was to identify children with TB and begin to treat them in such a way as to reduce the amount of time they spent in sanatoria. In part this was due to a shortage of beds. In 1947, having been appointed a Dublin Corporation TB officer, Dunlevy toured Norway and Sweden with three medical colleagues from Dublin Corporation's TB service to investigate the success of the BCG vaccine. By this time she had begun an x-ray and testing program to assess the infection rates and find where infection was most sourced.

The following year she was appointed assistant medical officer for Dublin city. She pointed out at the time that medical staff were paid less for tuberculin testing of patients than veterinarians were for the testing of cattle. Dunlevy had developed a reputation for rigour and organisation and was selected to pilot childhood BCG vaccination scheme in Dublin, her skills ensured the schemes effectiveness. TB deaths in children and pregnant women had risen during the war and reached a peak in 1947. Vaccination schemes had been tried before; the new pilot programme began in October 1948. By 1949 childhood deaths had reduced by two thirds. Dunlevy's program focused on statistics and data which enabled them to target specific households and areas for both treatment and vaccination. James Deeny said that Dunlevy built up from nothing the efficient, beautifully organised Dublin scheme, which ran like clockwork, was availed of produced no unfavourable incidents, reduced childhood tuberculosis to vanishing point, lowered the awful incidence of tuberculosis meningitis in babies in Dublin.

All this was carried out during the difficult postwar conditions in the city' A planned children's sanatorium became unnecessary and was turned into an adult facility due to the success of the scheme. Once the scheme was extended to include newborns at maternity hospitals the reduction in children's deaths from TB was over 82%; those doctors who followed the Scandinavian models saw impressive results. Those who took their lead from Britain were less successful; the new Department of Health, the state's chief medical officer James Deeny and minister for health, Noel Browne contributed to the success of the Dublin vaccination scheme. Dunlevy was appointed by the minister to the national vaccination committee which held its last meeting in December 1978. During her role as senior assistant chief medical officer in the Dublin Health Authority infectious diseases receded. One of the last major schemes in which she was involved was the rubella vaccination program beginning in 1971. Another was the combined diphtheria and pertussis vaccine.

The trials for the combined vaccine has since gained notoriety due to the lack of consent obtained for children who took part in the trials and were in state institutions at the time. Dunlevy went on, in 1971 until her retirement in 1976 to work as the deputy chief medical officer in the Eastern Health Board. Dunlevy was now an international expert in childhood epidemiology and published papers in the British Medical Journal, the Journal of the Medical Association of Éire, the Irish Journal of Medical Science, the Journal of the Irish Medical Association. Once retired Dunlevy wrote a regular column for the Irish Medical Times. Dunlevy was involved in the associations related to her expertise, she was president of the Biological Society of the RCSI in 1952, president of the Irish Society for Medical Officers of Health, on the committee of the'women's federation' of the Irish Medical Association. She was a member and fellow of the Royal College of Physicians of Ireland, a member of the faculty of community medicine of the RCPI, a fellow of the Royal Academy of Medicine of Ireland.

Dunlevy's elder sister Annie Josephine Dunlevy graduated from the RCSI and practised as a psychiatrist in Donegal and Dublin. She lectured in anatomy at the RCSI, she lived for many years at various Dublin addresses with her sister. She was the aunt of museum curator and costume expert Mairéad Dunlevy. Dunlevy had a long time companion Kat

Alarsite is an aluminium arsenate mineral with its name derived from its composition: aluminium and arsenate. It occurs as brittle subhedral grains, it has a Mohs hardness of 5-5.5 and a specific gravity of 3.32. It colorless with pale yellow tints and shows a vitreous luster, it is optically uniaxial with refractive indices of nω = 1.596 and nε = 1.608. It was reported from fumaroles in the Tolbachik volcano, Far Eastern Region, Russia, it occurs in association with fedotovite, lammerite, atlasovite, langbeinite and tenorite