howard turner rotary table quotation

Working in from the hand wheel, there is a knurled ring that looks separate from the hand wheel but won"t rotate without it. Integral with the knurled ring there is a scaled cylinder - rather like the markings on a lathe. But these are engraved 0 - then 15 divisions on - 30 - then another 15 division on - 1, and so on until you pass 3 and come back to zero after a full revolution of the hand wheel. Thus, I assume each of the 15 divisions between 0 and 30 represents two minutes and the 1 represents 60 minutes or one degree of table movement or four degrees per revolution of the hand wheel i.e. a ratio of 90:1 in terms of wheel to table revolutions.

After the aforementioned knurled ring and cylinder there"s another stepped cylinder that turns independently of the outer one. This is engraved, at random as far as I can see, with a scale 60 0 60, with three divisions to the left of the zero and three to the right. I assume these are seconds of one minute of one degree. Protruding vertically from the after part of this cylinder is a short lever that engages or disengages the worm drive to the table so you can turn the latter by hand, if so wished, without turning the hand wheel. A thumb screw on the body of the machine locks the worm in engagement.

By way of example of my frustration: If I want a bolt circle of three, what I would do is twirl the hand wheel until the pointer on the fixed base registers with zero on the annular ring on the bottom of the table. Then, twirl again to 120, do the business, twirl another 120 (240 on the scale) and so on. But this strikes me as very unsophisticated and negates the point of all the gubbins behind the hand wheel. So, anybody, how do you set it up to do, for the sake of argument, a segment of 60° 12" 30"?

The gear ratio for the Vertex HV6 Rotary table is 90:1, so 30 turns of the handle will give one third of a turn of the table, and so on, or use the degree scale on the edge of the table, so that you rotate the table the required number of degrees, (say 72 degrees, if you wanted five divisions, 60 degrees for 6 divisions, and so on). As long as you bring the Handwheel back to the same point every time, it will give an accurate result

Anyone having a Rotary Table, or Dividing Head with a ratio other than 90:1 has only to change the gear ratio, and the number of holes in the Division Plates, in the formulae, to have a spreadsheet for their equipment. (I HOPE!)

You may also want to look at the Grizzly manual for their H7527 RT, which also looks almost exactly like a Vertex 6", with the exception that this manual (and the one linked by Michael) illustrate a 4-slot table. My 12-year-old Vertex has only three slots. The H7527 manual also has a couple of pages on dividing, but double-check the numbers in the table before using them. It also illustrates two oiling points, one in the main body near the handwheel, and one in the side of the table. My RT also has an oil point on the top of the table near the centre hole, presumably for the main table bearing, although I have never seen it illustrated or mentioned in any docs.

Turning the worm the required number of times to complete one revolution of the table will always bring you back bang on your starting point, the main gear has exactly 360.000deg. It"s not like an Escher stairwell where you could vanish into another dimension before winding up back where you started. However, along the way, their are various errors that occur and can interact (e.g. cyclic errors in the worm itself, and the mating gear) to make an absolute determination of the exact angular position after some number of turns of the wheel an unlikely proposition. Offhand, I don"t think you"re likely to see accuracy or repeatability specs for any of the RTs at our level. They will, of course, quote the setting resolution (the markings on the wheel and collar, and any vernier graduations), but you can decide on the likely accuracy yourself.

Howard Robard Hughes Jr. (December 24, 1905 – April 5, 1976) was an American business magnate, record-setting pilot, engineer,eccentric behavior and reclusive lifestyle—oddities that were caused in part by his worsening obsessive-compulsive disorder (OCD), chronic pain from a near-fatal plane crash, and increasing deafness.

During his final years, Hughes extended his financial empire to include several major businesses in Las Vegas, such as real estate, hotels, casinos, and media outlets. Known at the time as one of the most powerful men in the state of Nevada, he is largely credited with transforming Vegas into a more refined cosmopolitan city. After years of mental and physical decline, Hughes died of kidney failure in 1976. His legacy is maintained through the Howard Hughes Medical Institute and the Howard Hughes Corporation.

Howard Robard Hughes Jr. was the son of Allene Stone Gano (1883–1922) and of Howard R. Hughes Sr. (1869–1924), a successful inventor and businessman from Missouri. He had English, Welsh and some French Huguenot ancestry,John Gano (1727–1804), the minister who allegedly baptized George Washington.

Hughes Sr. patented the two-cone roller bit in 1909, which allowed rotary drilling for petroleum in previously inaccessible places. The senior Hughes made the shrewd and lucrative decisions to commercialize the invention by: leasing the bits instead of selling them, obtaining several early patents, and founding the Hughes Tool Company in 1909.

His mother Allene died in March 1922 from complications of an ectopic pregnancy. Howard Hughes Sr. died of a heart attack in 1924. Their deaths apparently inspired Hughes to include the establishment of a medical research laboratory in the will that he signed in 1925 at age 19. Howard Sr."s will had not been updated since Allene"s death, and Hughes Jr. inherited 75% of the family fortune.emancipated minor, enabling him to take full control of his life.

By the end of 1954, Hughes had gained near-total control of RKO at a cost of nearly $24 million, becoming the first sole owner of a major Hollywood studio since the silent-film era. Six months later Hughes sold the studio to the General Tire and Rubber Company for $25 million. Hughes retained the rights to pictures that he had personally produced, including those made at RKO. He also retained Jane Russell"s contract. For Howard Hughes, this was the virtual end of his 25-year involvement in the motion-picture industry. However, his reputation as a financial wizard emerged unscathed. During that time period, RKO became known as the home of classic Noah Dietrich, Hughes made a $10,000,000 profit from the sale of the theaters and made a profit of $1,000,000 from his 7-year ownership of RKO.: 272–273

Originally known as Summa Corporation, the Howard Hughes Corporation formed in 1972 when the oil-tools business of Hughes Tool Company, then owned by Howard Hughes Jr., floated on the New York Stock Exchange under the "Hughes Tool" name. This forced the remaining businesses of the "original" Hughes Tool to adopt a new corporate name: "Summa". The name "Summa"—Latin for "highest"—was adopted without the approval of Hughes himself, who preferred to keep his own name on the business, and suggested "HRH Properties" (for Hughes Resorts and Hotels, and also his own initials). In 1988 Summa announced plans for Summerlin, a master-planned community named for the paternal grandmother of Howard Hughes, Jean Amelia Summerlin.

The H-1 Racer featured a number of design innovations: it had retractable landing gear (as Boeing Monomail had five years before), and all rivets and joints set flush into the body of the aircraft to reduce drag. The H-1 Racer is thoughtWorld War II fighters such as the Mitsubishi A6M Zero, Focke-Wulf Fw 190, and F8F Bearcat,Smithsonian.: 131–135

Shortly after founding the company, Hughes used the alias "Charles Howard" to accept a job as a baggage handler for American Airlines. He was soon promoted to co-pilot.

In 1948 Hughes created a new division of Hughes Aircraft: the Hughes Aerospace Group. The Hughes Space and Communications Group and the Hughes Space Systems Division were later spun off in 1948 to form their own divisions and ultimately became the Hughes Space and Communications Company in 1961. In 1953 Howard Hughes gave all his stock in the Hughes Aircraft Company to the newly formed Howard Hughes Medical Institute, thereby turning the aerospace and defense contractor into a tax-exempt charitable organization. The Howard Hughes Medical Institute sold Hughes Aircraft in 1985 to General Motors for $5.2 billion. In 1997 General Motors sold Hughes Aircraft to Raytheon and in 2000, sold Hughes Space & Communications to Boeing. A combination of Boeing, GM, and Raytheon acquired the Hughes Research Laboratories, which focused on advanced developments in microelectronics, information & systems sciences, materials, sensors, and photonics; their work-space spans from basic research to product delivery. It has particularly emphasized capabilities in high-performance integrated circuits, high-power lasers, antennas, networking, and smart materials.

Other aviator awards include: the Bibesco Cup of the Fédération Aéronautique Internationale in 1938, the Octave Chanute Award in 1940, and a special Congressional Gold Medal in 1939 "in recognition of the achievements of Howard Hughes in advancing the science of aviation and thus bringing great credit to his country throughout the world".

Critics nicknamed the Hercules the Spruce Goose, but it was actually made largely from birch (not spruce) rather than from aluminum, because the contract required that Hughes build the aircraft of "non-strategic materials". It was built in Hughes"s Westchester, California, facility. In 1947, Howard Hughes was summoned to testify before the Senate War Investigating Committee to explain why the H-4 development had been so troubled, and why $22 million had produced only two prototypes of the XF-11. General Elliott Roosevelt and numerous other USAAF officers were also called to testify in hearings that transfixed the nation during August and November 1947.TWA"s route awards and malfeasance in the defense-acquisition process, Hughes turned the tables on his main interlocutor, Maine Senator Owen Brewster, and the hearings were widely interpretedMcMinnville, Oregon, where as of 2020Evergreen Aviation & Space Museum.: 198–208

Hughes and Charnay"s most published dealings were with a contested AirWest leveraged buyout. Charnay led the buyout group that involved Howard Hughes and their partners acquiring Air West. Hughes, Charnay, as well as three others, were indicted.SEC by paying former stockholders for alleged losses from the sale of their investment in Air West stock.Hughes Airwest. During a long pause between the years of the dismissed charges against Hughes, Charnay, and their partners, Howard Hughes mysteriously died mid-flight while on the way to Houston from Acapulco. No further attempts were made to file any indictments after Hughes died.

In 1953, Hughes launched the Howard Hughes Medical Institute in Miami, Florida, (currently located in Chevy Chase, Maryland) with the expressed goal of basic biomedical research, including trying to understand, in Hughes"s words, the "genesis of life itself", due to his lifelong interest in science and technology. Hughes"s first will, which he signed in 1925 at the age of 19, stipulated that a portion of his estate should be used to create a medical institute bearing his name.Verne Mason, who treated Hughes after his 1946 aircraft crash, was chairman of the institute"s medical advisory committee.

Hughes dated many famous women, including Joan Crawford, Debra Paget, Billie Dove, Faith Domergue, Bette Davis, Yvonne De Carlo, Ava Gardner, Olivia de Havilland, Katharine Hepburn,Hedy Lamarr, Ginger Rogers, Janet Leigh, Pat Sheehan,Mamie Van Doren and Gene Tierney. He also proposed to Joan Fontaine several times, according to her autobiography No Bed of Roses. Jean Harlow accompanied him to the premiere of Hell"s Angels, but Noah Dietrich wrote many years later that the relationship was strictly professional, as Hughes disliked Harlow personally. In his 1971 book, Howard: The Amazing Mr. Hughes, Dietrich said that Hughes genuinely liked and respected Jane Russell, but never sought romantic involvement with her. According to Russell"s autobiography, however, Hughes once tried to bed her after a party. Russell (who was married at the time) refused him, and Hughes promised it would never happen again. The two maintained a professional and private friendship for many years. Hughes remained good friends with Tierney who, after his failed attempts to seduce her, was quoted as saying "I don"t think Howard could love anything that did not have a motor in it". Later, when Tierney"s daughter Daria was born deaf and blind and with a severe learning disability because of Tierney"s exposure to rubella during her pregnancy, Hughes saw to it that Daria received the best medical care and paid all expenses.

Meier, in collaboration with former Vice President Hubert Humphrey and others, wanted to feed misinformation to the Nixon campaign. Meier told Donald that he was sure the Democrats would win the election because Larry O"Brien had a great deal of information on Richard Nixon"s illicit dealings with Howard Hughes that had never been released;Terry Lenzner, who was the chief investigator for the Senate Watergate Committee, speculates that it was Nixon"s desire to know what O"Brien knew about Nixon"s dealings with Hughes that may have partially motivated the Watergate break-in.

While directing Jane Russell"s blouses, claiming that the fabric bunched up along a seam and gave the appearance of two nipples on each breast. He wrote a detailed memorandum to the crew on how to fix the problem. Richard Fleischer, who directed Just Tell Me When to Cry, Fleischer explained that Hughes was fixated on trivial details and was alternately indecisive and obstinate. He also revealed that Hughes"s unpredictable mood swings made him wonder if the film would ever be completed.

After the screening room incident, Hughes moved into a bungalow at the Beverly Hills Hotel where he also rented rooms for his aides, his wife, and numerous girlfriends. He would sit naked in his bedroom with a pink hotel napkin placed over his genitals, watching movies. This may have been because Hughes found the touch of clothing painful due to allodynia. He may have watched movies to distract himself from his pain—a common practice among patients with intractable pain, especially those who do not receive adequate treatment.

Hughes began purchasing restaurant chains and four-star hotels that had been founded within the state of Texas. This included, if for only a short period, many unknown franchises currently out of business. He placed ownership of the restaurants with the Howard Hughes Medical Institute, and all licenses were resold shortly after.

Hughes insisted on using tissues to pick up objects to insulate himself from germs. He would also notice dust, stains, or other imperfections on people"s clothes and demand that they take care of them. Once one of the most visible men in America, Hughes ultimately vanished from public view, although tabloids continued to follow rumors of his behavior and whereabouts. He was reported to be terminally ill, mentally unstable, or even dead.

Following his death, Hughes was subject to several widely rebuked conspiracy theories that he had faked his own death. A notable allegation came from retired Major General Mark Musick, Assistant Secretary of the Air Force, who claimed Hughes went on to live under an assumed identity, dying on November 15, 2001, in Troy, Alabama.

Approximately three weeks after Hughes"s death, a handwritten will was found on the desk of an official of the Church of Jesus Christ of Latter-day Saints in Salt Lake City, Utah. The so-called "Mormon Will" gave $1.56 billion to various charitable organizations (including $625 million to the Howard Hughes Medical Institute), nearly $470 million to the upper management in Hughes"s companies and to his aides, $156 million to first cousin William Lummis, and $156 million split equally between his two ex-wives Ella Rice and Jean Peters.

Hughes"s $2.5 billion estate was eventually split in 1983 among 22 cousins, including William Lummis, who serves as a trustee of the Howard Hughes Medical Institute. The Supreme Court of the United States ruled that Hughes Aircraft was owned by the Howard Hughes Medical Institute, which sold it to General Motors in 1985 for $5.2 billion. The court rejected suits by the states of California and Texas that claimed they were owed inheritance tax.

The moving image collection of Howard Hughes is held at the Academy Film Archive. The collection consists of over 200 items including 35mm and 16mm elements of feature films, documentaries, and television programs made or accumulated by Hughes.

mini-series on the CBS network, made a year after Hughes"s death and based on Noah Dietrich"s book Howard: The Amazing Mr. Hughes. Tommy Lee Jones plays Hughes.

Jonathan Demme and starring Jason Robards as Howard Hughes and Paul Le Mat as Melvin Dummar. The film won Academy Awards for Best Original Screenplay (Bo Goldman) and Best Supporting Actress (Mary Steenburgen). The film focuses on Melvin Dummar"s claims of meeting Hughes in the Nevada desert and subsequent estate battles over his inclusion in Hughes"s will. Critic Pauline Kael called the film "an almost flawless act of sympathetic imagination".

In The Rocketeer, a 1991 American period superhero film from Walt Disney Pictures, the title character attracts the attention of Howard Hughes (played by Terry O"Quinn) and the FBI, who are hunting for a missing jet pack, as well as Nazi operatives.

"Howard Hughes Documentary", broadcast in 1992 as an episode of the Time Machine documentary series, was introduced by Peter Graves, later released by A&E Home Video.

In Mel Gibson) mentions one of his theories to a street vendor by saying, "Did you know that the whole Vietnam War was fought over a bet that Howard Hughes lost to Aristotle Onassis?" referring to his (Fletcher"s) thoughts on the politics of that conflict.

Howard Hughes: The Real Aviator documentary was broadcast in 2004 and went on to win the Grand Festival Award for Best Documentary at the 2004 Berkeley Video & Film Festival.

The American Aviator: The Howard Hughes Story was broadcast in 2006 on the Biography Channel. It was later released to home media as a DVD with a copy of the full-length film Jane Russell.

Dominic Cooper), a wealthy inventor of futuristic technology, clearly embodying Hughes"s persona and enthusiasm. His subsequent appearances in the TV series Stan Lee has noted that Howard"s son Tony Stark (Iron Man), who shared several of these traits himself, was based on Hughes.

Stan Lee repeatedly stated he created the Marvel Comics character Iron Man"s civilian persona, Tony Stark, drawing inspiration from Howard Hughes"s colorful lifestyle and personality. Additionally, the first name of Stark"s father is Howard.

The 1973 song ”Broadway melody of 1974” by Genesis referenced Howard Hughes: ”There"s Howard Hughes in blue suede shoes / Smiling at the majorettes, smoking Winston cigarettes”.

The song "Ain"t No Fun (Waiting "Round To Be a Millionaire)" by AC/DC on their 1976 album "Dirty Deeds Done Dirt Cheap" singer Bon Scott referenced Howard Hughes toward the end of the song: "Hey, hello Howard, how you doin", my next door neighbour? Oh, yea... Get your fuckin" jumbo jet off my airport"

The 1996 album "Thanks for the Ether" by Rasputina features a song titled "Howard Hughes" about Hughes" eccentricities and isolation in his later life.

Beeney, Bill (March 8, 1972). "The Mail Goes Through But Flavor Is Gone". The Democrat Chronicle. Rochester, New York: Newspapers.com. p. 31. Our facility residence is in the 4000 block on Yoakum Blvd. The building next to it at 3900 is the Modern Language Department, It is the former Howard Hughes home. We paid $82,000 cash for it about 10 years ago.

"William Durkin; rescued Howard Hughes in crash." Archived July 23, 2012, at the Wayback Machine Boston.com, May 2, 2006. Retrieved: January 17, 2012.

Tennant, Forest (July–August 2007). "Howard Hughes & Pseudoaddiction" (PDF). Practical Pain Management. Montclair, New Jersey: PPM Communications, Inc. 6 (7): 12–29. Archived from the original (PDF) on September 25, 2007. Retrieved January 7, 2011.

"Howard Hughes and TWA"S Constellations – Airways Magazine". Airways Magazine. June 6, 2016. Archived from the original on January 11, 2018. Retrieved January 10, 2018.

Brooks, John (December 23, 1973). "The strange case of T.W.A. vs. Howard Hughes vs. T.W.A." The New York Times. ISSN 0362-4331. Retrieved January 10, 2018.

"Howard Hughes" auto kills man in Hollywood." Archived November 7, 2012, at the Wayback Machine Chicago Tribune, July 12, 1936. Retrieved: December 13, 2009.

David Garonzik (Director), Leonardo DiCaprio, Jeffrey M. Schwartz, Donald L. Barlett (Actors) (May 24, 2005). The Affliction of Howard Hughes: Obsessive-Compulsive Disorder. Los Angeles, California: Miramax. Archived from the original on October 20, 2014. Retrieved August 13, 2018 – via YouTube.

"Howard Hughes Revealed". Archived September 7, 2009, at the Wayback Machine hulu.com, via National Geographic Channel, Inside (series), Season 7, episode 2. Retrieved: September 24, 2009.

Turner, Suzanne; Wilson, Joanne Seale (March 22, 2010). Houston"s Silent Garden: Glenwood Cemetery, 1871-2009. Texas A&M University Press. ISBN 9781603441636 – via Google Books.

Shannon, Jeff. "Melvin and Howard (1980) – Movie Preview." Archived September 27, 2007, at the Wayback Machine RopeofSilicon, 2008. Retrieved: August 5, 2008.

Barton, Charles. Howard Hughes and his Flying Boat. Fallbrook, CA: Aero Publishers, 1982. Republished in 1998, Vienna, VA: Charles Barton, Inc. ISBN 0-9663175-0-5.

Barlett, Donald L. and James B. Steele. Empire: The Life, Legend and Madness of Howard Hughes. New York: W.W. Norton & Company, 1979. ISBN 0-393-07513-3, republished in 2004 as Howard Hughes: His Life and Madness.

Bellett, Gerald. Age of Secrets: The Conspiracy that Toppled Richard Nixon and the Hidden Death of Howard Hughes. Stillwater, Minnesota: Voyageur Press, 1995. ISBN 0-921842-42-2.

Drosnin, Michael. Citizen Hughes: In his Own Words, How Howard Hughes Tried to Buy America. Portland, Oregon: Broadway Books, 2004. ISBN 0-7679-1934-3.

Maheu, Robert and Richard Hack. Next to Hughes: Behind the Power and Tragic Downfall of Howard Hughes by his Closest Adviser. New York: HarperCollins, 1992. ISBN 0-06-016505-7.

HOUSTON– Three Big Ten Conference defensive standouts and one Big XII offensive lineman make up the four finalists for the 37th Rotary Lombardi Award, presented by Wachovia. The annual honor, which benefits the American Cancer Society, will be presented on December 6 at the Hilton Americas Hotel in Downtown Houston. Tickets are on sale now through the Rotary Club of Houston at (713) 973-9936.

“Our finalists dominate on the football field and stand as examples of hard work, discipline and support on their teams and in their communities,” said E. Michelle Bohreer, General Chair of the 37th Rotary Lombardi Award Committee. “Those are the characteristics so valued and respected by Coach Lombardi.”

Founded in the weeks following the death of legendary football coach Vince Lombardi from cancer in 1970, the Rotary Lombardi Award presented by Wachovia Bank has annually delivered upon the mission set forth by Marie Lombardi when she first granted the use of her late husband’s name. Her only stipulation was that all net proceeds from the event be donated to the American Cancer Society, and millions of dollars have been raised since that time.

This year’s Rotary Lombardi Award is being presented by Wachovia Bank, which is in the second year of a two-year presentation sponsorship agreement with the Rotary Club of Houston Foundation to support the event and its fund raising component. Tables and individual tickets are now on sale through the Rotary Club of Houston office (713) 973-9936.

This article is intended as an introduction to an issue devoted to biological rotary nanomotors. It provides a historical perspective on the study of rotation of the bacterial flagellum, the first—and for more than 20 years the only—known biological rotary motor. It has recently become clear that rotary motors on a molecular scale are everywhere in nature. It is this realization that inspired the review and perspective articles that are compiled in this issue.

The curtain that blocked our view of rotation in living organisms was raised in 1973. In a paper appearing in Nature, Howard Berg and Robert Anderson presented the idea that flagella, thin helical filaments used for motility by bacteria, propel the cells by rotating (Berg and Anderson, 1973). They reasoned from available information. The paper features one hand-drawn figure, thereby extending a precedent set by Watson and Crick 20 years earlier (Watson and Crick, 1953).

Berg and Anderson had two irrefutable pieces of evidence for rotation. A swimming Escherichia coli cell is pushed by a bundle of 4–6 flagellar filaments. The first evidence for rotation was provided by the observation that when divalent antibody prepared against flagellar filaments was added to swimming cells, the cells immediately stopped swimming. The interpretation was that their flagellar filaments became crosslinked and could no longer slide past one another as they must in a bundle of rotating filaments. When monovalent antibody raised against the filament was added, motility was retained. The interpretation was that the filaments became thicker when they bound the monovalent antibody but could still slide past one another as they rotated in a bundle.

Figure 1. (A) Diagram of an E. coli cell. E. coli is a rod-shaped, gram-negative bacterium. It has an inner and outer membrane with a thin but relatively rigid peptidoglycan (PG) cell wall in the periplasmic space between the two membranes. The four to six flagella arise at random points along lateral surface of the cell cylinder. The proximal hook serves as a universal joint to allow rotation of the flagellum perpendicular to the cell envelope to bend 90° so that the left-handed helical flagellar filaments can come together to form a bundle that pushes the cell. The nucleoid is shown in green, and the chemoreceptor patches at the cell poles are shown in orange. The patch at the old pole is larger. In this image it is at the leading end of the cell, although the old pole can be either at the leading or trailing end (Berg and Turner, 1995). (B) The three-dimensional random walk. The image at the left shows a two-dimensional projection of a cell that is running and tumbling in three dimensions. The image to the right shows a cell that is swimming in a gradient of an attractant chemical with a higher concentration at the top. The runs in the up-gradient direction are longer than in the image to the left, whereas the runs in the down-gradient direction are of the same length. The shorter runs in the absence of an attractant gradient provide space for Howard Berg to look on approvingly from the upper left.

These discoveries came just at the time that the behavior of swimming cells was being recorded automatically by the tracking microscope invented by Howard Berg (1971). The tracking microscope had been used to show that E. coli cells swim in a behavior first called running and twiddling (Figure 1B), with twiddles later being called tumbles (Berg and Brown, 1972). The cells swim on a path (the run) that is as straight as can be given the rotational diffusion of an object as small as an E. coli cell. They then go through a brief period of chaotic motion (the twiddle or tumble) that reorients them before the onset of the next run. The average change in heading is about 68°, slightly biased in the direction the cell had been heading. Both runs and tumbles show an exponential length distribution, with the mean run lasting about 1 s and the mean tumble about 0.1 s. This behavior was aptly described as a 3-dimensional random walk.

The bacterial flagellum is a complex machine (Figure 2). In E. coli, the products of about 40 genes (Table 1) are required to construct a fully functional flagellum. In other species, particularly those with very rapidly rotating flagella (e.g., Vibrio species) or internal periplasmic flagella (spirochetes), other proteins are required, but the basic set of parts remains the same. Most of the gene products are designated as Flg, Flh, or Fli, depending on where on the chromosome the encoding genes are located. Four of these proteins are transcriptional regulators. Others are required only transiently during the assembly of the flagellum. Two of them, MotA and MotB, are not required to build a flagellum but are required for it to rotate. They are of special interest because they comprise a common element, presumably evolved from a common ancestral gene, that is found in several rotary motors discussed in this issue that are coupled to processes other than flagellar rotation.

It was the discovery of the rotating stator that provided the impetus for compiling an issue devoted to rotary nanomachines. Various aspects of flagella are the topics of seven articles. Four articles consider systems that operate with homologs of MotAB that are coupled to functions other than flagellar motility: movement over surfaces by gliding bacteria, transport of large substrates across the outer membrane of gram-negative bacteria, and cell division. Two articles consider a structure that superficially looks like a flagellum but is functionally and evolutionarily completely distinct: the ATP-hydrolysis-driven archaellum of the Archaea. Finally, seven articles discuss the rotary FoF1 ATP synthase. Evidence to support the idea that this enzyme in E. coli is a rotary device was presented by the laboratory of Paul Boyer in 1987 (Kandpal and Boyer, 1987) and demonstrated to be a rotary device by direct observation in 1997 (Noji et al., 1997). The energy for all of these rotary machines other than the archaellum is provided by a transmembrane ion motive force that drives the coupling ion down its potential energy gradient into the cell. This issue celebrates both rotary nanomachines and the life of Howard Berg, who departed us on December 30, 2021. Enjoy.

Berg, H. C., and Turner, L. (1995). Cells of Escherichia coli swim either end forward. Proc. Natl. Acad. Sci. U. S. A 92, 477–479. doi: 10.1073/pnas.92.2.477

Block, S. M., and Berg, H. C. (1984). Successive incorporation of force-generating units in the bacterial rotary motor. Nature 309, 470–472. doi: 10.1038/309470a0

Zhou, J., Sharp, L. L., Tang, H. L., Lloyd, S. A., Billings, S., Braun, T. F., et al. (1998b). Function of protonatable residues in the flagellar motor of Escherichia coli: a critical role for Asp 32 of MotB. J. Bacteriol. 180, 2729–2735. doi: 10.1128/JB.180.10.2729-2735.1998