9^ On (he Difertnce of Level between the 



Bertou has thus read off no smaller parts than whole lines ; 

 and neither the temperature of the barometer, nor that of the 

 air, seems to have been determined. His observations, there- 

 fore, have no claim to great accuracy.* Notwithstanding this, 

 and perhaps other deficiencies in the measurements, the great 

 height of 20J Parisian inches, observed at the Dead Sea, can 

 only be explained by its low position. 



In the Comptes Eeiidus, vol. vii. p. 798, M. Callier has cal- 

 culated the above-mentioned height of the barometer (which, 

 however, he gives as only TO/'"'".^, instead of 798™"'.5G), and 

 thence, assuming 760™"^.0 as the mean height of the barome- 

 ter at the level of the sea, he has deduced 406 metres =1249.8 

 Parisian feet (about 1330 English feet) for the depression of 

 the Dead Sea ; which is more than double the amount assigned 

 by Professor Schubert. 



Shortly after his first excursion to the Dead Sea, a little 

 air unfortunately entered M. Bertou's barometer, and he there- 

 fore performed his subsequent measurements, during a journey 

 from Hebron to Akaba and back again, by means of the boil- 

 ing point of water, as determined by a thermometer of Lede- 



larly, was not adapted to such observations) ascend beyond the scale. We 

 were obliged to calculate the height by the eye, and although we reduced the 

 calculation as much as possible, owing to the extremely unexpected nature 

 of the result, yet the level of the Dead Sea hence deduced, was at least 6984, 

 or, in round numbers, GOO Parisian feet : that is nearly 640 English feet un- 

 der that of the Mediterranean. We endeavoured to explain away this con- 

 clusion in every possible way. First of all, we supposed an accidental un- 

 usually high state of the barometer on the very day of our observation ; but 

 the previous day's storm ought rather to have produced a fall than a rise of 

 the mercury. We next imagined that there must be something wrong with 

 our instrument, exposed as it had been to so many mischances ; but, on our 

 return to Jerusalem, it exhibited the same mean height as before our jour- 

 ney to Jericho. Notwithstanding all this, however, I could not have ven- 

 tured to make public so extraordinary a measurement after my return home, 

 although the measurement of the height of the Lake of Tiberias corresponded 

 with it, had it not been, that some of my friends published a notice of it 

 in the Allgemeine Zeitung. And scarcely had this taken place, when imme- 

 diately public confirmations made their appearance, of the abnormal depres- 

 sion of the Dead or Salt Sea, first of all from Mr Beek, and afterwards from 

 other observers ; confirmations which, nevertheless, make our determination 

 appear the most moderate." (Vol. iii. p. 80). — Editor. 



* M. Bertou himself is surprised at the great difference of the results for 

 Sidoii and Acre, two places lying on the sea-coast. 



