The David Rumsey Historical Map Collection has over 8,800 maps online. The collection focuses on rare 18th and 19th century North and South America maps and other cartographic materials. Historic maps of the World, Europe, Asia and Africa are also represented. Collection categories include antique atlas, globe, school geography, maritime chart, state, county, city, pocket, wall, childrens and manuscript maps. The collection can be used to study history, genealogy and family history.
From the Multi-Repository Mathematics Collections site you will gain access to three of the most significant mathematics collections digitally available: The Mathematics Collection from Cornell, the Mathematics Collection from Göttingen, and the University of Michigan's Historical Math Collection. From this access point you will be able to search across all three of these collections, and examine results as you would normally using the University of Michigan's user interface. It is important to point out that the University of Göttingen has only one item for which a fulltext search can be performed, but bibliographic searches across the collection are possible.
The reader will, I hope, agree that the "almost-antiseptic" washing machines of today don't have nearly the charm nor the character, albeit hazardous character, of those our grandmothers used. Our presentation herein is focused on the elegant washing machines which were powered either with gasoline engines or electric motors and were in use from 1900-1935. In 1920 there were over 1300 companies producing washers, and it is feasible here to show only a sampling of the myriad designs and shapes produced. Selected for illustration, are about 5% of the machines in my "hobby museum" located in Eaton, Colorado. Indeed, there is a lot more to see.
Until quite recently, I though that the first published HR diagram was constructed by Ejnar Hertzsprung for the stars of the Pleiades. Already in 1908, when Hertzsprung (then still an amateur astronomer with training in photochemistry) visited Karl Schwarzschild at Göttingen, he brought with him a working version with photographic magnitudes plotted against effective wavelengths. To determine the latter quantity, nowadays replaced by spectral type or color index, Hertzsprung attached a coarse diffraction grating before the objective so that an ordinary stellar image on the photographic plate was accompanied by a very short first-order spectrum on either side. The separation of the most intense parts of these spectra then directly translated into the effective wavelength of the star's light. However, this first Hertzsprung attempt to visualize the relation between luminosities and colors of stars suffered from a systematic error due to influence of the secondary spectrum of the objective. It was not until 1911, when the satisfactory version of the diagram was presented (Publ. Astrophys. Observ. Potsdam 22, 1, 1911) together with a color-magnitude diagram for another winter cluster, the Hyades.
n the Third Annual Report of the Henry Draper Memorial, attention is called to the fact that the K line in the spectrum of Zeta Ursae Majoris occasionally appears double. The spectrum of this star has been photographed at the Harvard College Observatory on seventy nights and a careful study of the results has been made by Miss. A. C. Maury, a niece of Dr. Draper. The K line is clearly seen to be double in the photographs taken on March 29, 1887, on May 17, 1889 and on August 27 and 28, 1889. On many other dates the line appeared hazy, as if the components were slightly separated, while at other times the line appears to be well defined and single.
This website contains material useful to people studying the history of the CA/T highway, especially the Charles River crossing part of the project. During 1998, we operated an interactive website for the purpose of collecting original material from people who were involved in planning the crossing. Some comments and articles contributed by people involved in the crossing design process are available on-line. Other material at this website includes a chronology of planning the crossing, a chronological bibliography of important transportation documents with links to some of these, and images. Hardcopy material pertaining to the crossing is available in the vertical file collection at M.I.T.'s Rotch Library.
This site presents a historical overview of the Massachusetts Highway Department's Central Artery/Tunnel Project for downtown Boston, known commonly as the "Big Dig." In particular, the site focuses on the northern part of the project linking Cambridge and Charlestown with Boston over the Charles River. Documents surrounding the planning, testing, legal wrangling and execution of the project are listed chronologically. The site also includes maps and other images relating to the project's development, and several recollections by transportation engineers, civil engineers and others who worked on the project and had to accommodate the conflicting interests of residents, builders and government planners.
Last year saw two interesting events in the world of double stars, both of them connected with an astronomer's old friend in the Big Dipper. While the early history of double star astronomy had to be completely rewritten after an examination of 17th century Italian manuscripts, its future at the beginning of the next millennium was briefly unveiled by the amazing precision of a new astrometric instrument, which will soon eliminate the difference between spectroscopic and visual binaries.
Established in 1879 to build and organize a collection of scientific materials in the earth sciences, the U.S. Geological Survey Library is now the largest library for earth sciences in the world. The library system includes four libraries and is part of the Geographic Information Office of the USGS.
The United States Geological Survey (USGS) Library is the largest earth science library in the world. The library serves the research needs of USGS scientists throughout the nation and provides information to other organizations and individuals in the areas of geology, hydrology, cartography, biology, and related fields. USGS libraries are located in Reston, Virginia; Denver, Colorado; Menlo Park, California; and Flagstaff, Arizona. The site provides search engines for the library catalogue, USGS and other government maps, and the USGS minerals collection. Special Collections include field notes, photographs, sketches, logs, reports and maps dating from 1879. The page is broken down into useful sub-pages and is easily navigated.
What is a polymerase? A polymerase is a naturally occurring enzyme, a biological macromolecule that catalyzes the formation and repair of DNA (and RNA). The accurate replication of all living matter depends on this activity -- an activity scientists have learned to manipulate. In the 1980s, Kary Mullis at Cetus Corporation conceived of a way to start and stop a polymerase's action at specific points along a single strand of DNA.
This site covers the history of a critical technology for modern genetic and biological research. Polymerase chain reaction, or PCR, is a method for manipulating, splicing and replicating, in vast amounts, sequences of DNA and RNA. The author of the site, a professor at UCLA, has written an overview essay on the history of PCR in which he points to a wide array of advances and scientists who contributed to its creation. Supporting this essay is a bibliography linked to many of the groundbreaking articles relating to PCR from the latter part of the twentieth century, as well as its first uses in genome mapping, evolutionary biology and medical treatments. The site also includes an interview with Arthur Kornberg, a key figure in the history of recombinant DNA and biotechnology, and it asks for additional recollections from those who have been a part of the development of PCR and its many applications.
This web site is an online gateway to the extraordinary library resources of Harvard University and serves as an important research tool for Harvard's current students, faculty, staff, and researchers who hold Harvard IDs and PINs. The site also provides practical information on each of the more than 90 libraries that form the Harvard system. Visitors and guests should consult the Library's Frequently Asked Questions before navigating the sit
