EVENTS

Members Reports and Photos

SATURDAY 25th JANUARY 2014            

GEOLOGY MUSEUM TRINITY COLLEGE  

LEADER: PATRICK WYSE JACKSON

Geological Museum Visit, and a Tour of the Building Stones of the Campus

Dr Patrick Wyse Jackson, a former President of the Field Club, is Associate Professor of Geology and Curator of the Geology Museum. His main interests are in fossils and his research area has focused on bryozoans that range in age from the Ordovician to the Recent, with particular emphasis on Mississippian faunas.

The meeting commenced in the hallway of the museum building where the exhibits in the glass-fronted display cases were viewed and explained by Patrick. We then proceeded to the Geological Museum. The Geological Museum is situated on the top floor of the Department of Geology. The Museum collections date from 1777, and comprise about 80,000 specimens. The main palaeontological holdings include Irish Silurian and Carboniferous invertebrates, Mesozoic ostracods, and Upper Palaeozoic miospores. The mineral collection largely dates from the 1820s and contains both Irish and foreign specimens. The exhibition The Story of the Earth contains displays covering the complete range of geological topics. More than an hour was spent viewing the exhibits but so great was the interest that as one member remarked: “You could spend an hour viewing one case”. 

Patrick explained the important early contributions made by Irish scientists to the very polarising 19th Century topic of the age of the earth:
John Joly, who hailed from Co Offaly, was a former Professor of Geology and Mineralogy at Trinity College proposed to calculate the age of the earth from the accumulation of sodium in the waters of the oceans. He calculated the rate at which the oceans should have accumulated sodium from erosion processes, and determined that the oceans were about 80 to 100 million years old. Although this method was later considered inaccurate and was consequently superseded, it radically modified the results of other methods in use at the time.

William Thompson (Lord Kelvin) from Belfast, published in 1862 calculations that estimated the age of Earth at between 20 million and 400 million years. He assumed that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface to cool to its present temperature. His calculations did not account for heat produced via radioactive decay (a process then unknown to science) or convection inside the Earth, which allows more heat to escape from the interior to warm rocks near the surface.  

More than an hour was spent viewing the exhibits and Patrick provided much information and answered many questions from the partcipants. So great was the interest that one member remarked: “You could spend an hour viewing one case”. 

We then proceeded to view the building from the top town as Patrick pointed out some of the features of particular interest. The Museum Building, which houses the Geology Department, was designed by Thomas Deane and Benjamin Woodward. It is inspired by the Byzantine architecture of Venice and was built in 1853-57. The many interior and exterior carvings were executed by the Cork-born brothers John and James O'Shea, who gathered fresh flowers to use as their models. The exterior walls feature Wicklow granite and Portland Stone. The interior walls are faced with Caen Limestone. The pillars, balustrades and bannisters contain examples of Irish marbles and Cornish serpentine, while the domed roof is made of blue, red and yellow enamelled bricks. There are plans to use this magnificent building as an exhibition centre.

The final part of the visit included a look at the outside of the Old Library building which had been recently cleaned and the meeting concluded at the Examinations Hall where a discussion was held about the about the campanile and the origin of the cobblestones in Front Square officially known as Parliament Square which was originally funded by the Irish Parliament.  


          

Museum Building                       Museum Door                      Geology Museum

    

Initials of Architect and Builder                                      Carving by O'Shea Brothers

        

                      Zinc Mining                               Zinc-products                      Map of Mines                            John Joly                                    
                          

     

                     Ediacaran fossils                                         Gneiss (Mayo)                                                  Dingle fossils          

...   

Nautilus pompilius                                                  Pillow Lava

  ........   

            Coal from Castlecomer                                  Fluoorescent minerals 

       

Cooksonia plant fossil               "Diplopodocus and "Tyrannosaurus"                     Plesiosaurus macrocephalus

        

Fern fossil             Clubmoss fossil                               Gingo biloba & fossil                          Horsetail fossil

         

Sun-coral                       Titanites giganteus fossil                                              "Triceratops"

Photos © P Lenihan and others

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