Among scientists studying seismology the famous Moho-layer (or Moho-discontinuity) of the Earth is well known. It was named after the great Croatian geophysicist Andrija Mohorovicic (born in Volosko, 1857-1936), professor at the University of Zagreb. His discovery was essential for understanding the inner structure of the Earth and the behavior of seismic waves. Together with the theory of forces due to Rudjer Boskovic, this is probably the greatest achievement in the history of Croatian science.

Let us cite a part of his biography from Willard Basom’s monograph A hole in the Bottom of the Sea, The story of the MOHOLE project, 1959/61, Doubledays, USA (p. 143):

…As a boy of 15 he spoke Italian, French, and English as well as his native Croatian, later added German, Czech, Latin, and old Greek. He studied physics at the University of Prague under some famous professors including E. Mach and did his graduate work at the University of Zagreb, from which he obtained a Ph.D. In 1894 Dr. Mohorovicic became Director of the Institute for Meteorology and Geodynamics and Professor at the University of Zagreb in 1897, where he remained until his retirement in 1921. His special interest was the precise measurement of time for both astronomical and seismical events, but his reputation mainly rests on his classic paper in the field of seismology, The Earthquake of October 8, 1909, which contains the news of his discovery of a major discontinuity at a depth of 55 kilometers. This discontinuity, now generally known as the Moho in his honor, defines the crust of the earth. Professor Mohorovicic died in 1936 in circumstances approaching poverty.

Photo from an article by Mete Oner: Deepest borehole ever drilled

Andrija Mohorovicic around 1902,
 photo from 150 godina Geofizickog zavoda, ur. Mirko Orlic, Zagreb 2011.

Two Croatian names appear on the map of the Moon. The name of Rudjer Boskovic was given to a mountain on the visible side, and the name of Andrija Mohorovicic to a mountain on the dark side of the Moon.

Andrija Mohorovičić

The title of the 1925 article published by Kiyoo Wadati, distinguished Japanese sesmologist:”On Mohorovičić Wave appeared in Tazima-Earthquake“,  Journal of the Meteorological Society of Japan (web). Ser. II Vol. 3(1925) No. 8, 201-211.
See [PDF]. Many thanks to Yoko Nishii for kindly providing the links pointing to the article and the journal.

From the abstract of the article: “Some seismograms of the destructive earthquake occurred on May 23rd, 1925 in North Tazima district, show distinctly so-called the Mohorovičić wave. One of them is shown in Fig. (4) magnified from the seismograms of Wiechert’s 200kg. seismograph installed at the Central Meteorological Observatory in Tokyo. (Epicenter distance about 450km.) …”

Note that the name of Mohorovičić appears already in the title.

Many thanks to Professor Mirko Orlic (of the Croatian Academy of Sciences and Arts) for this photo. 

Kiyoo Wadati also published another article related to the work of Mohorovičić: “On the Mohorovicic Wave Observed in Japan.” Geophysical Magazine 1 (1927): 87–96.

Here is the name of Andrija Mohorovičić written in Japanese, provided by the courtesy of Yoko Nishii.

Memorial plaque in the Prague dedicated to Andrija Mohorovičić, where he has studied at the Charles University (among his professors was famous Ernst Mach). Photo from Marijan Lipovac and Vlatka Banek: Hrvatsko-češko društvo / prvih 25 godina, Zagreb 2017, by the courtesey of Mr. Lipovac.

As a student in the Prague, Andrija Mohorovičić was a founder and secretary of the Society of Croatian Students Hrvat (Hrvat = Croat), established in 1876.

Andrija Mohorovicic, links

Mohorovic made pioneering observations of rotor-type circulation (or atmospheric rotor, with horizontal axis) in bora. For more information see the following article:

• Vanda Grubisic and Mirko Orlic: Early observations of rotor clouds by Andrija Mohorovicic [PDF], Bulletin of the American Meteorological Society (vol. 88, 2007, str. 693-700) [many thanks to dr. Orlic, University of Zagreb, for the PDF]
  

Other references related to Andrija Mohorovičić:

• Video of a public lecture by Mirko Orlic and his colleagues (in Croatian).
• Kroz koru do plašta / Nove spoznaje o Andriji Mohorovičiću (1857.-1936.), Hrvatska akademija znanosti i umjetnosti (Croatian Academy of Sciences and Arts), Zagreb 2019.