Fejér László – Lászlóffy Woldemár: A hidrometria magyarországi fejlődése (1700-1945) (Vízügyi Történeti Füzetek 13. Budapest, 1986)
Idegen nyelvű összefoglalók
LISTOF FIGURES 1. Measurement of flow velocity by means of connected floats. Excerpt from Leonardo da VINCI's notes, around 1500 A. D. 2. Instruments of flow velocity measurement in the 1 7th and 18th centuries: 1. Lorgna's water measuring device; 2. Ximenes's water flag; 3. Brunings's tachometer; 4. Woltman's current meter vane; 10. Spherical float; 12—13. Measuring device with vane wheel; 14. Cabeo's floating stick; 15. Floating string; 16—17. Pitot tube; Guglielmini's flow measurement quadrant. 3. Ornament from MARSIG Li's book. At the stern of the boat the stylized picture of a flow measurement quadrant can be seen. 4. Cross-section of the Danube at Pétervárad. 5. Reconstruction of the original Woltman-type current meter. 6. LEUPOLD's measuring devices. The concept of two instruments shown in the upper part of the picture is identical with the principle of Michelotti's rapid balance. 7. Drawing of the Pitot tube in Károly HADALY's text-book on hydraulic construction. The cone-like extension of the tube belonging to the instrument on the left served to attain higher measurement accuracy. 8. Experimental flow velocity measurements performed by Mátyás HUSZÁR and Lajos BERGER in 1825 on the Danube at Pozsony. 9. First representation of isotach lines, the curves connecting the points of equal flow velocity within a cross-section; this was first presented in printed form in Prof. WIESENFELD's report on the Danube measurements. PÁL VÁSÁRHELYI Lithograph by Miklós BARABÁS from 1846. 10. Results of a discharge measurement executed between the 16th and 31th October in 1838 in the Buda cross-section of the Danube (at the present Szabadság Bridge). Text on the drawing: „Danubian discharge measuring cross-section No. 248, 688 fathoms [1304 m] downstream of the Buda gauge at the Salt Store. Width at water stage 4'10"6"' [154 cm] above zero level of the Buda gauge is 161° [306 m]. Q. — 21,048 [cross-section area below the water stage prevailing during measurement is 2105m 2 ], q = 20.480' [cross-section area below reduced water level is 2048 m 2 ), M —48.211 e " [1522 m 3 /s]". Flow velocities measured along verticals with spacing of 3 fathoms (5.7 m) at depths increased by 3 feet (0.95 nh) are indicated in the drawing in feet. Values given for the bottom did not originate from direct measurement but — with VÁSÁRHELYI's words —: "... they were determined by using the concept of interpolation; because, as it is known, due to inaccessibility the velocities at the bottom cannot be measured practically." József PETZELT Lithograph by Miklós BARABÁS from 1846. 11. Woltman-type current meter made by Antal NUSS, mechanician at Pest. Gyula RÉVY with his family. 12. Amsler—Laffon-made Woltman-type current meter — from the 1870s — in disassembled form. 13. Drawing of Gyula RÉVY's instrument rod, from his work published in 1874. 14. RÉVY's instrument, fabricated in the 1870s by the London firm Elliott.
