74 Scientific Intelligence. [July, 



These tables form a very useful supplement to those of M. 

 Chernac, which have the same form, and are sold in the same 

 place. This task which appears immense, and which must have 

 been particularly disagreeable on account of its uniformity, was 

 performed at spare hours, and facilitated by simple and ingenious 

 methods which rendered it at once shorter and more accurate. 

 After the example of Lambert the author has contented himself 

 with giving the smallest divisor of every number, from which the 

 greatest may be immediately deduced by an easy division. To have 

 all the other divisions it is sufficient to seek for the quotient in the 

 table of M. Chernac. 



After the actual division which enables us to find by repeated 

 essays the smallest divisor of each number, the first method that 

 presents itself is that of constructing by simple additions tables of 

 the multiples of all the prime numbers, stopping at the multiple 

 which would pass the limits of the projected tabic. But this labour 

 would be merely preparatory^ it would remain to transcribe in 

 another order the whole table, and there would be a great many 

 useless numbers, because it has been agreed upon to suppress in all 

 these sorts of tables all the numbers divisible by 2, 3, and 5, be- 

 cause they may be known by simple inspection. By the arrange- 

 ment which the author has contrived to give to his preparatory 

 tables, the divisors 7 and 11, which occur more frequently than 

 any of the others, are similarly placed in all the pages. A copper 

 plate engraved was sufficient for all this part of the table. M. 

 Burckhardt successivelyemployed, and has shortly explained in his 

 preface, different contrivances, some of which were already known, 

 while others belong to himself exclusively, and had escaped Euler 

 who had condescended to write a long memoir on the composition 

 of these tables. The goodness of such a work depends upon the 

 care with which it has been printed. M. Daussy divided with the 

 author the labour of revising the proof sheets. M. Daussy is 

 known for a patient ar.d skilful calculator; we are indebted to him 

 for the elements of different comets. We may therefore expect to 

 find these tables as exact as they can be made by the labour of man. 



Article X. 

 SCIENTIFIC intelligence; and notices of subjects 



CONNECTED WITH SCIENCE. 



I. Singular Disease. 



In the country of the Nogays, a tribe of Tartars dwelling between 



the Black Sea and the Caspian, on the south side of the river 



Kuma, there still exists a very singular disease, which is mentioned 



by Herodotus, and several of the other ancienl Greek writers- 



