39S. yotices respecting Xev; Buoki. 



Lunar and Horary Tables for nev: and concise Methods ofpa^ 

 Jbrming the Calcidations necessarij for ascertainijig the Lon- 

 gitude by Lunar Observations or Chronometers ; "with ati 

 Appendix, containing directions for acquiring a knoiicledge 

 of the principal Fixed Stars. By David Thomson, inventor 

 of the Longitude Scale. — Kingsbury & Co. London ; Oliver 

 and Hoyd, Edinburgh. Price \0s. 



These Tables for clearing the lunar distances from the ef- 

 fects of parallax and refraction, are designed to facilitate the 

 computations necessary for ascertaining the longitude; and they 

 certainly appear to us to be better adapted to that object than 

 any of the various methods with which we are accjuainted : 

 they are at once concise and simple ; little is left to the know- 

 ledge or discretion of the calculator; every thing is ready 

 performed to his hand ; neither too itiuch is given nor too 

 little; — and, what is of some importance, all contained within 

 a thin octavo volume, at the price of ten shillings, — so that 

 it will come within the reach of seamen in general. One 

 particular excellence, which is seldom to be met with in me« 

 thods founded on the same principle, and which must be highly 

 approved by navigators, is, that there is no distinction of cases, 

 — all the corrections on account of parallax and refraction 

 are additive. We have not been able to enter into a detailed 

 investigation of the tables, nor has the author stated the prin- 

 ciples of their construction and application. " 



Prof Schumacher, with a laudable zeal for the promotion of 

 science and its application to objects of utility, has in his Ephe- 

 meris extended our means of comparison by inserting the 

 distances of the different planets from the moon ; and we think 

 it important that no encouragement should be wanting to in- 

 duce the navigator on all occasions to practise the lunar ob- 

 servations as the best, because the only certain means of ascer- 

 taining the place of his ship : any method which diminishes 

 the number of mechanical operations requisite to be performed 

 in the reduction of an observation, without the sacrifice of sim- 

 plicity will be extremely serviceable towards bringing this 

 much neglected method into more general practice at sea. 



Recently j^ublished. 



Memoirs of Moses Mendelsohn, the Jewish Philosopher; 

 including the celebrated correspondence on the Christian Re- 

 ligion with J. C. Lavater, Minister of Zurich. By M. Samuels. 

 Longman and Co. 



The Century of Inventions of the Marquis of Worcester. 

 From the original MS. With historical and explanatory Notes 

 and a Biographical Memoir. By Charles F. Partington. 



COL- 



