Intelligence and Miscellaneous Articles. 145 



that will happen in the course of the year j together with all the ne- 

 cessary elements for computing them. This is followed by three pages 

 of the principal phaenomena of the planets : such as the time of their 

 perigee or apogee, their perihelion or aphelion, their greatest elon- 

 gation, their greatest latitude, their conjunction and opposition, their 

 passing the nodes, their greatest brilliancy, their proximity to the 

 moon and occultation thereby, &c. 



Then follows a list of moon-culminating stars, occupying seventeen 

 pages ; and (which is equally valuable,) a list of the occultations of 

 all the stars down to the 7th magnitude inclusive, that will take place 

 in the course of the year ; wherein the mean time of the immersion 

 and emersion of the star (to the nearest tenth of a minute) is given, 

 as well as the angle from the vertex of the moon at which the phe- 

 nomenon will take place. To this list is subjoined some auxiliary 

 tables for computing the occultation more minutely, if required. 



To the whole is annexed an Appendix, giving an account of the 

 mode in which all the computations are made, and the tables from 

 which they are derived. By this excellent plan, the observer Can at 

 any time verify any of the calculations, and detect any error which he 

 may have cause to suspect. The names of the computers also are 

 given, which must materially tend to insure the accuracy of the work. 



Such is the substance of the publication now before us, which has 

 just reached this country, and which does so much credit to its di- 

 stinguished conductor. We hail it as the harbinger of a general im- 

 provement in the mode of arranging and forming the ephemerides of 

 different nations. And although it is mortifying to reflect that this 

 country cannot (or will not) maintain its pre-eminence in these and 

 other scientific subjects, yet we are grateful for information wherever 

 it can be found, and trust that we shall be able eventually to emulate 

 the splendid example which has thus been set us. M. Encke, disdain- 

 ing the trammels of former and less enlightened times, and relying 

 on his own excellent judgement and abilities, has nobly and boldly 

 struck out a new path for himself, which we have no doubt will soon 

 be followed by every nation pretending to encourage the science of 

 astronomy. , 



We propose to give, in a subsequent Number of our Journal, a 

 translation of the Appendix above alluded to, which will enable the 

 English reader to make use of this most excellent Ephemeris ; since 

 a very minute account is there given of the mode in which the dif- 

 ferent tabular values are formed. There will then be nothing left for 

 explanation but the headings of the different columns j which are in 

 most cases so much like the English names, that little difficulty will 

 occur in understanding them. 



IMPROVED AIR-PUMP. BY MR. JOHN DUNN, OPTICIAN, EDIN- 

 BURGH. 



In the course of my business, having often heard it regretted that 

 the cost of apparatus prevented many gentlemen from engaging in 

 philosophical pursuits, I have made it my study to simplify the con- 



New Series. Vol. 4. No. 20. Aug. 1828. U struction 



