308 Notices respecting New Books. 



when the subject treated of is a science in a state of such rapid 

 advance as Modern Chemistry. On the other hand, however, the 

 likelihood of the publication being spread over an unnecessarily long 

 period is greater under this system than when the publishers feel 

 that they are to some extent breaking faith with their subscribers if 

 a certain number of pages does not appear on a certain day. It 

 thus sometimes happens that the beginning and the end of the same 

 book represent very different stages in the development of a science, 

 as in the case of the Handw or ter bitch der reinen und angewandten 

 Chemie, the publication of which commenced in 1837, and is now 

 nearly completed. In contrast with this system is that which has 

 been adopted in the case of Mr. Watts's Dictionary, and is the one 

 usually adopted, as far as practicable, in the publication of English 

 works of a similar character, namely, the issue of Parts of a uni- 

 form size at regular intervals of time. This mode of publication 

 ensures the completion of the work within a limited period after the 

 appearance of the first Part ; but since it is necessary, in order to 

 prevent subsequent delay, that the printing of the whole work should 

 be far advanced before any portion is published, the earlier Parts 

 must be already somewhat behind the actual state of the science by 

 the time they reach the purchaser's hands. The method of publica- 

 tion which would combine to the greatest possible extent the advan- 

 tages of the two foregoing systems, while excluding their disadvan- 

 tages, would be, in the first place, to complete the manuscript of the 

 whole work ; then to proceed with the printing at such a rate as 

 would allow the author or editor ample time not only to correct the 

 press, but to make such alterations in or additions to each por- 

 tion of copy, before delivering to the printer, as may have become 

 necessary since it was first written ; lastly, to issue the work as fast 

 as it is printed, keeping the press only so much in advance of the 

 publication as may be deemed necessary to allow for accidental and 

 extraordinary delays. 



So far as we can judge by internal evidence, the composition of 

 the volume before us appears to have been completed about the end of 

 the year 1861, the latter portions showing but very few important 

 omissions in respect to information published before that date ; the 

 matter contained in the first two or three Parts, on the other hand, 

 has not always been brought down to a later date than about the 

 end of 1859. Throughout the volume, however, the information 

 contained in the various articles is very complete up to a certain 

 point ; so that it is only fair to suppose that the reason why the 

 whole volume has not been completed up to a still later period, was 

 the necessity of going early to press in order to render possible the 

 rapid issue of the work. The value of a work of reference, con- 

 taining so great a mass of facts as this does, is of course not very 

 materially lessened by its not containing a few more, if only it 

 is complete in all important points so far as it goes, and this 

 Mr. Watts's Dictionary seems to be in an eminent degree. It 

 would, however, often be a great convenience if every volume of 

 such works bore, besides the date of publication, the date up 



