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Account o/' a Wooden Suspension-Dial used in the Alps and 

 Pyrenees. By Owen Stanley, Esq. R. N. With a Figure. 

 Communicated by the Author. 



This Htttle wooden instrument is used in the neighbourhood of 

 Barege in the Pyrenees, and there it is called the Barege clock. 

 Calculated for that latitude, it was a mere object of curiosity in 

 our latitude ; but conceiving that it might, if the shadow points 

 in the curves could be calculated for any latitude, become an 

 article of general use and ready sale, my friend the Rev. Mr 

 Stanley, who sent me specimens of these dials, and suggested 

 what has just been stated, transmitted for the Journal the fol- 

 lowing notice of the principle and mode of construction of the 

 instrument, drawn up by Mr Stanley, one of the officers of Cap- 

 tain King^s exploratory expedition, which is here subjoined. 



Cyhnder CKB, Fig. 2. Plate III., is suspended from the 

 point C by a thread, when the line AB (which is at right angles 

 to AD) will become horizontal, and coincide with the visible 

 horizon ABH. 



The ffnomon or index is fixed into the moveable head of the 



o 



instrument, so as to revolve round the cylinder at right angles 

 to its axis. 



The dial is used as follows : Turn the gnomon round until 

 it is immediately over the line denoting the day of the month ; 

 let the cylinder hang freely from the point C, and turn it round 

 until the shadow of the gnomon falls on the line immediately 

 under it, then the end of the shadow will mark the hour by its 

 position with respect to the hour lines 2 E, 3 F, 4 G, &c. 



Construction. — On the cylinder draw 18 parallel lines, at 

 equal distances ; the extreme line at one end representing the 

 21st of December, at the other end the 21st of June, and the 

 intermediate lines every- tenth day. On the line representing 

 the 21st of June, from the line AK, with a radius equal to the 

 length AB of the gnomon, lay off' the tangents of the sun's al- 

 titude corresponding to the hours 4, 5, 6, &c. the declination 

 23, 30, and the latitude of the place, (which altitudes may be 

 taken by inspection from Lynn's Horary Tables). On the next 

 line to the right, which will represent the 11th of June or the 

 1st of July, (because the sun will have the same declination on 



JULY SEPTEMBER 1831. T 



