Works by Dr. Gregory, published by J. Conder. 



however, confined himself to a bare translation, but has 

 given many valuable notes, which add considerably to the 

 utility of the work." Phil. Mag. Dec. 1307. 



2. Dll. GREGORY'S TREATISE ON ASTRONOMY > 

 in which the Elements of the Science aie deduced in a na- 

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For testimonies in faveur of this Treatise, see Monthly 

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 tical Repository and Review, Sept. 1802. 



3 DR. GREGORY'S TREATISE OE MECHANICS^ 

 THEORETICAL, PRACTICAL, AND; DESCRIPTIVE; 

 in two large octavo volumes, besides a vlume containing 

 fifty-five quarto plates. The first volume isdeveted to the 

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 and Pneumatics : the second volume contains Remarks en 

 the Nature, Construction, and Simplification of Machinery, 

 n Friction, and the Rigidity of Cords, First Movers, &c. 

 with Tables, and Descriptions of nearly twe hundred cu- 

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 boards. 



Commendatory accounts of this extensive work are given 

 in Phil. Mag. No. 95. Crit. Rev. May 1806. Brit. Crit. 

 Aug. 1806. M'onth. Rev. March 1807. Annual Rev. for 

 1806. Eclectic Rev. Nov. 1307. 



4. In conjunction with Dr. HUTTON, volume Third of 

 A COURSE OF MATHEMATICS, composed for the Use 

 of the Royal Military Academy, by Order of his" Lordship 

 the Master-General of the Ordnance, price 12s. bound. 



5 In conjunction with JOHN MASON GOOD, Esq. F. R. S. 



.and Mr. NEWTON BOSWORTH, 



PANTOLOGIA : a General Dictionary of Arts, Sciences, 

 and Words: now re-publishing in Monthly Parts, and 

 completed in 12 vols. Royal octavo. 



6. LETTERS TO A FRIEND ON THE EVIDENCES, 

 DOCTRINES, AND DUTIES OF THE CHRISTIAN 

 RELIGION. In 2'vels. crown' 8vo. 3d edition. 14s. boards. 



This work is intended to guard young persons of liberal edu- 

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 ful tendency to influence 



