sentence-transformers/squad huggingface dataset:
Passage: The question of priority for the variable resistance feature of the telephone was raised by the examiner before he approved Bell's patent application. He told Bell that his claim for the variable resistance feature was also described in Gray's caveat. Bell pointed to a variable resistance device in Bell's previous application in which Bell described a cup of mercury, not water. Bell had filed the mercury application at the patent office a year earlier on February 25, 1875, long before Elisha Gray described the water device. In addition, Gray abandoned his caveat, and because he did not contest Bell's priority, the examiner approved Bell's patent on March 3, 1876. Gray had reinvented the variable resistance telephone, but Bell was the first to write down the idea and the first to test it in a telephone.

Question: What part of the telephone was investigated by the patent officer?

Question: When did Bell put in his prior patent?

Question: What liquid did Bell use in his first application?
Passage: The patent examiner, Zenas Fisk Wilber, later stated in an affidavit that he was an alcoholic who was much in debt to Bell's lawyer, Marcellus Bailey, with whom he had served in the Civil War. He claimed he showed Gray's patent caveat to Bailey. Wilber also claimed (after Bell arrived in Washington D.C. from Boston) that he showed Gray's caveat to Bell and that Bell paid him $100. Bell claimed they discussed the patent only in general terms, although in a letter to Gray, Bell admitted that he learned some of the technical details. Bell denied in an affidavit that he ever gave Wilber any money.

Question: Who declared himself an alcoholic?

Question: In what war did Wilber and Bailey fight together?

Question: How much did Wilber say Bell gave him in order to look at Gray's paperwork?

Question: What did Bell only admit to knowing in a letter?
Passage: Continuing his experiments in Brantford, Bell brought home a working model of his telephone. On August 3, 1876, from the telegraph office in Mount Pleasant five miles (eight km) away from Brantford, Bell sent a tentative telegram indicating that he was ready. With curious onlookers packed into the office as witnesses, faint voices were heard replying. The following night, he amazed guests as well as his family when a message was received at the Bell home from Brantford, four miles (six km) distant, along an improvised wire strung up along telegraph lines and fences, and laid through a tunnel. This time, guests at the household distinctly heard people in Brantford reading and singing. These experiments clearly proved that the telephone could work over long distances.

Question: From what city did Bell send his first message?

Question: Bell sent messages over wires hooked onto telegraph lines and what?

Question: What did the group at the Bells house hear other people doing?
Passage: Bell and his partners, Hubbard and Sanders, offered to sell the patent outright to Western Union for $100,000. The president of Western Union balked, countering that the telephone was nothing but a toy. Two years later, he told colleagues that if he could get the patent for $25 million he would consider it a bargain. By then, the Bell company no longer wanted to sell the patent. Bell's investors would become millionaires, while he fared well from residuals and at one point had assets of nearly one million dollars.

Question: How much did Bell et al. try to sell his patent for?

Question: Who did Bell et al. try to sell his patent to?

Question: What did the President think the telephone was, such that he refused to buy the patent?

Question: How much the the President of Western Union want to pay for the patent later on?
Passage: Bell began a series of public demonstrations and lectures to introduce the new invention to the scientific community as well as the general public. A short time later, his demonstration of an early telephone prototype at the 1876 Centennial Exposition in Philadelphia brought the telephone to international attention. Influential visitors to the exhibition included Emperor Pedro II of Brazil. Later Bell had the opportunity to demonstrate the invention personally to Sir William Thomson (later, Lord Kelvin), a renowned Scottish scientist, as well as to Queen Victoria, who had requested a private audience at Osborne House, her Isle of Wight home. She called the demonstration "most extraordinary". The enthusiasm surrounding Bell's public displays laid the groundwork for universal acceptance of the revolutionary device.

Question: In what city was the 1876 Centennial Exposition?

Question: What important person saw the telephone at the Centennial Exposition?

Question: Pedro II was the Emperor of what Country?

Question: Which Queen did Bell present his invention to?
Passage: The Bell Telephone Company was created in 1877, and by 1886, more than 150,000 people in the U.S. owned telephones. Bell Company engineers made numerous other improvements to the telephone, which emerged as one of the most successful products ever. In 1879, the Bell company acquired Edison's patents for the carbon microphone from Western Union. This made the telephone practical for longer distances, and it was no longer necessary to shout to be heard at the receiving telephone.

Question: In what year was the Bell Telephone Company founded?

Question: How many people in the United States had a telephone by 1886?

Question: In what year did Bell get some of Edison's patents?

Question: What addition let people stop yelling into the telephone?

Question: What company did Bell acquire the carbon microphone from?
Passage: In January 1915, Bell made the first ceremonial transcontinental telephone call. Calling from the AT&T head office at 15 Dey Street in New York City, Bell was heard by Thomas Watson at 333 Grant Avenue in San Francisco. The New York Times reported:

Question: In what month and year did Bell telephone across the country?

Question: What company office did Bell make the original cross country phone call from?

Question: What city did Bell make the first cross country call from?

Question: What city did Bell make the first cross country call to?

Question: Who was on the other end of the first cross country phone call?
Passage: As is sometimes common in scientific discoveries, simultaneous developments can occur, as evidenced by a number of inventors who were at work on the telephone. Over a period of 18 years, the Bell Telephone Company faced 587 court challenges to its patents, including five that went to the U.S. Supreme Court, but none was successful in establishing priority over the original Bell patent and the Bell Telephone Company never lost a case that had proceeded to a final trial stage. Bell's laboratory notes and family letters were the key to establishing a long lineage to his experiments. The Bell company lawyers successfully fought off myriad lawsuits generated initially around the challenges by Elisha Gray and Amos Dolbear. In personal correspondence to Bell, both Gray and Dolbear had acknowledged his prior work, which considerably weakened their later claims.

Question: During how many years did the Bell Company battle lawsuits?

Question: How many times were Bell's patents contested?

Question: How many of the court cases wound up at the Supreme Court?

Question: Elisha Gray and what other man were behind many of the court cases?
Passage: On January 13, 1887, the U,S. Government moved to annul the patent issued to Bell on the grounds of fraud and misrepresentation. After a series of decisions and reversals, the Bell company won a decision in the Supreme Court, though a couple of the original claims from the lower court cases were left undecided. By the time that the trial wound its way through nine years of legal battles, the U.S. prosecuting attorney had died and the two Bell patents (No. 174,465 dated March 7, 1876 and No. 186,787 dated January 30, 1877) were no longer in effect, although the presiding judges agreed to continue the proceedings due to the case's importance as a "precedent". With a change in administration and charges of conflict of interest (on both sides) arising from the original trial, the US Attorney General dropped the lawsuit on November 30, 1897 leaving several issues undecided on the merits.

Question: In 1887 the US Government wanted to undo Bell's patent due to fraud and what?

Question: The US Government lost the bid to overturn Bell's patent in what court?

Question: How many years did Bell and the US Government fight in court?

Question: What excuse did the judges have for the trial despite the fact that the patents had expired?

Question: On what date did the US Government stop legal action?
Passage: During a deposition filed for the 1887 trial, Italian inventor Antonio Meucci also claimed to have created the first working model of a telephone in Italy in 1834. In 1886, in the first of three cases in which he was involved, Meucci took the stand as a witness in the hopes of establishing his invention's priority. Meucci's evidence in this case was disputed due to a lack of material evidence for his inventions as his working models were purportedly lost at the laboratory of American District Telegraph (ADT) of New York, which was later incorporated as a subsidiary of Western Union in 1901. Meucci's work, like many other inventors of the period, was based on earlier acoustic principles and despite evidence of earlier experiments, the final case involving Meucci was eventually dropped upon Meucci's death. However, due to the efforts of Congressman Vito Fossella, the U.S. House of Representatives on June 11, 2002 stated that Meucci's "work in the invention of the telephone should be acknowledged", even though this did not put an end to a still contentious issue.[N 17] Some modern scholars do not agree with the claims that Bell's work on the telephone was influenced by Meucci's inventions.[N 18]

Question: Who claimed to have invented the in 1834?

Question: How many court trials did Meucci participate in?

Question: At what company were Meucci's prototypes supposedly lost?

Question: In what year did Western Union absorb ADT?

Question: What event caused Meucci's trials to be dropped?
Passage: The value of the Bell patent was acknowledged throughout the world, and patent applications were made in most major countries, but when Bell had delayed the German patent application, the electrical firm of Siemens & Halske (S&H) managed to set up a rival manufacturer of Bell telephones under their own patent. The Siemens company produced near-identical copies of the Bell telephone without having to pay royalties. The establishment of the International Bell Telephone Company in Brussels, Belgium in 1880, as well as a series of agreements in other countries eventually consolidated a global telephone operation. The strain put on Bell by his constant appearances in court, necessitated by the legal battles, eventually resulted in his resignation from the company.[N 19]

Question: Because of their patent, what didn't Siemens & Halske have to give Bell?

Question: What was the home city for the International Bell Telephone Company?

Question: In what year was the International Bell Telephone Company founded?
Passage: On July 11, 1877, a few days after the Bell Telephone Company was established, Bell married Mabel Hubbard (1857–1923) at the Hubbard estate in Cambridge, Massachusetts. His wedding present to his bride was to turn over 1,487 of his 1,497 shares in the newly formed Bell Telephone Company. Shortly thereafter, the newlyweds embarked on a year-long honeymoon in Europe. During that excursion, Bell took a handmade model of his telephone with him, making it a "working holiday". The courtship had begun years earlier; however, Bell waited until he was more financially secure before marrying. Although the telephone appeared to be an "instant" success, it was not initially a profitable venture and Bell's main sources of income were from lectures until after 1897. One unusual request exacted by his fiancée was that he use "Alec" rather than the family's earlier familiar name of "Aleck". From 1876, he would sign his name "Alec Bell". They had four children:

Question: Who did Bell marry in 1877?

Question: How many children did Bell and Mabel have?

Question: Where did Bell and his wife go on their honeymoon?

Question: Before 1897, what did Bell get most of his money from?
Passage: The Bell family home was in Cambridge, Massachusetts, until 1880 when Bell's father-in-law bought a house in Washington, D.C., and later in 1882 bought a home in the same city for Bell's family, so that they could be with him while he attended to the numerous court cases involving patent disputes.

Question: In what year did Mabel's father move to Washington D.C.?

Question: In what year did Bell acquire a house in D.C.?

Question: Where did Bell and Mabel live before 1880?

Question: What did Bell have to go to court for in D.C.?
Passage: Bell was a British subject throughout his early life in Scotland and later in Canada until 1882, when he became a naturalized citizen of the United States. In 1915, he characterized his status as: "I am not one of those hyphenated Americans who claim allegiance to two countries." Despite this declaration, Bell has been proudly claimed as a "native son" by all three countries he resided in: the United States, Canada, and the United Kingdom.

Question: In what year did Bell officially become an American?

Question: What was Bell's original nationality?

Question: Besides the US and UK, what other country claims Bell as a citizen?

Question: What does Bell call people who are citizens of two countries?
Passage: By 1885, a new summer retreat was contemplated. That summer, the Bells had a vacation on Cape Breton Island in Nova Scotia, spending time at the small village of Baddeck. Returning in 1886, Bell started building an estate on a point across from Baddeck, overlooking Bras d'Or Lake. By 1889, a large house, christened The Lodge was completed and two years later, a larger complex of buildings, including a new laboratory, were begun that the Bells would name Beinn Bhreagh (Gaelic: beautiful mountain) after Bell's ancestral Scottish highlands.[N 21] Bell also built the Bell Boatyard on the estate, employing up to 40 people building experimental craft as well as wartime lifeboats and workboats for the Royal Canadian Navy and pleasure craft for the Bell family. An enthusiastic boater, Bell and his family sailed or rowed a long series of vessels on Bras d'Or Lake, ordering additional vessels from the H.W. Embree and Sons boatyard in Port Hawkesbury, Nova Scotia. In his final, and some of his most productive years, Bell split his residency between Washington, D.C., where he and his family initially resided for most of the year, and at Beinn Bhreagh where they spent increasing amounts of time.

Question: What Island in Nova Scotia did the Bells go to in 1885?

Question: In 1886, what lake did Bell start building a house near?

Question: What did the Bells call the house completed in 1889?

Question: How many people worked for the Bell Boatyard?
Passage: Until the end of his life, Bell and his family would alternate between the two homes, but Beinn Bhreagh would, over the next 30 years, become more than a summer home as Bell became so absorbed in his experiments that his annual stays lengthened. Both Mabel and Bell became immersed in the Baddeck community and were accepted by the villagers as "their own".[N 22] The Bells were still in residence at Beinn Bhreagh when the Halifax Explosion occurred on December 6, 1917. Mabel and Bell mobilized the community to help victims in Halifax.

Question: Where did the Bells live when the Halifax Explosion happened?

Question: On what day did the Halifax Explosion happen?

Question: Which of their two homes did the Bells start spending more time as Bell aged?

Question: What city adopted the Bells?

Question: What did the Bells do to help the victims in Halifax?
Passage: Although Alexander Graham Bell is most often associated with the invention of the telephone, his interests were extremely varied. According to one of his biographers, Charlotte Gray, Bell's work ranged "unfettered across the scientific landscape" and he often went to bed voraciously reading the Encyclopædia Britannica, scouring it for new areas of interest. The range of Bell's inventive genius is represented only in part by the 18 patents granted in his name alone and the 12 he shared with his collaborators. These included 14 for the telephone and telegraph, four for the photophone, one for the phonograph, five for aerial vehicles, four for "hydroairplanes" and two for selenium cells. Bell's inventions spanned a wide range of interests and included a metal jacket to assist in breathing, the audiometer to detect minor hearing problems, a device to locate icebergs, investigations on how to separate salt from seawater, and work on finding alternative fuels.

Question: What series of books does Gray say Bell would go to sleep reading?

Question: How many solo patents did Bell get?

Question: How many patents did Bell co-author?
Passage: Bell worked extensively in medical research and invented techniques for teaching speech to the deaf. During his Volta Laboratory period, Bell and his associates considered impressing a magnetic field on a record as a means of reproducing sound. Although the trio briefly experimented with the concept, they could not develop a workable prototype. They abandoned the idea, never realizing they had glimpsed a basic principle which would one day find its application in the tape recorder, the hard disc and floppy disc drive and other magnetic media.

Question: What famous lab did Bell spend time working for?

Question: What type of energy did Bell investigate at the Volta Laboratory?

Question: The magnetic field is part of what sort of recorder?
Passage: Bell's own home used a primitive form of air conditioning, in which fans blew currents of air across great blocks of ice. He also anticipated modern concerns with fuel shortages and industrial pollution. Methane gas, he reasoned, could be produced from the waste of farms and factories. At his Canadian estate in Nova Scotia, he experimented with composting toilets and devices to capture water from the atmosphere. In a magazine interview published shortly before his death, he reflected on the possibility of using solar panels to heat houses.

Question: What form of water played a part in Bell's home cooling system?

Question: What did Bell think could be collected from farm and factory byproduct?

Question: What kind of toilet did Bell work on?

Question: Right before his death, what kind of energy did he speculate about?
Passage: Bell and his assistant Charles Sumner Tainter jointly invented a wireless telephone, named a photophone, which allowed for the transmission of both sounds and normal human conversations on a beam of light. Both men later became full associates in the Volta Laboratory Association.

Question: What did Bell call his cord-free phone?

Question: Who did Bell invent the cord-free phone with?

Question: What did Bell's cord-free phone use to transmit messages?

Question: What lab association did Bell and Tainter both eventually join?

Question: In the photophone, light carried sound and what?
Passage: On June 21, 1880, Bell's assistant transmitted a wireless voice telephone message a considerable distance, from the roof of the Franklin School in Washington, D.C., to Bell at the window of his laboratory, some 213 metres (700 ft) away, 19 years before the first voice radio transmissions.

Question: Bell and his assistant first used their photophone on what date?

Question: How many feet did the first photophone message travel?

Question: From what building was the first photophone message sent?

Question: How many years after this photophone message would the first message take place over radio?
Passage: Bell believed the photophone's principles were his life's "greatest achievement", telling a reporter shortly before his death that the photophone was "the greatest invention [I have] ever made, greater than the telephone". The photophone was a precursor to the fiber-optic communication systems which achieved popular worldwide usage in the 1980s. Its master patent was issued in December 1880, many decades before the photophone's principles came into popular use.

Question: What did Bell call the best thing he ever made?

Question: Bell thought the photophone was better than what famous invention?

Question: What modern technology takes the next step from the photophone?

Question: When was fiber-optics first patented?

Question: In what decade did fiber-optics become widely used?
Passage: Bell is also credited with developing one of the early versions of a metal detector in 1881. The device was quickly put together in an attempt to find the bullet in the body of U.S. President James Garfield. According to some accounts, the metal detector worked flawlessly in tests but did not find the assassin's bullet partly because the metal bed frame on which the President was lying disturbed the instrument, resulting in static. The president's surgeons, who were skeptical of the device, ignored Bell's requests to move the president to a bed not fitted with metal springs. Alternatively, although Bell had detected a slight sound on his first test, the bullet may have been lodged too deeply to be detected by the crude apparatus.

Question: What did Bell create in 1881?

Question: What was in James Garfield that they wanted to get out?

Question: What did Bell think was wrong with the bed, which prevented his machine from finding the bullet?

Question: On which run did Bell's metal detector give a small indication?

Question: When did Bell's metal detector work well?
Passage: Bell's own detailed account, presented to the American Association for the Advancement of Science in 1882, differs in several particulars from most of the many and varied versions now in circulation, most notably by concluding that extraneous metal was not to blame for failure to locate the bullet. Perplexed by the peculiar results he had obtained during an examination of Garfield, Bell "...proceeded to the Executive Mansion the next morning...to ascertain from the surgeons whether they were perfectly sure that all metal had been removed from the neighborhood of the bed. It was then recollected that underneath the horse-hair mattress on which the President lay was another mattress composed of steel wires. Upon obtaining a duplicate, the mattress was found to consist of a sort of net of woven steel wires, with large meshes. The extent of the [area that produced a response from the detector] having been so small, as compared with the area of the bed, it seemed reasonable to conclude that the steel mattress had produced no detrimental effect." In a footnote, Bell adds that "The death of President Garfield and the subsequent post-mortem examination, however, proved that the bullet was at too great a distance from the surface to have affected our apparatus."

Question: Bell gave his story about trying to find the bullet to the American Association for the Advancement of what?

Question: Where did Bell go the day after trying to find the bullet?

Question: What kind of mattress was the President directly on?

Question: Where did Bell indicate that the bullet was too deep for his machine to register?