OF METEOROLOGICAL INSTRUMENTS. 



FIG. 13. Fm. 15 



14. Gun Barometer^ being a special modification of No. 12, to enable it to withstand 



the concussion arising from the discharge of the largest modern guns on board 

 ships of war at sea. This is really the ne plus ultra of marine barometers, 

 possessing the utmost attainable accuracy combined with the best security 

 against breakage. It is expressly made for H. M.'s service . 5 10 



15. STANDARD MOUNTAIN BAEOMETEE, on the same principle as the Standard Baro- 



meter No. 1, but much reduced in size of frame, by which it is rendered 

 so portable as to remove nearly every difficulty hitherto found by travellers in 

 carrying a mercurial barometer. With English and millimetre scale and tripod 

 stand, complete, in CASELLA'S improved leather-covered shield case (figs. 15 

 and 15*) . . . . . . 8 10 



If -without case 25s. less. 



*#* A verification from the Boyal Kew Observatory is supplied with any of the preceding 

 standard or marine barometers, if required, at an extra charge of 7s. 6d. to 12s. 6d. 



