362 



NATURE 



[Feb. 20, 1879 



"(18) The complete composition of lymph, chyle, and 



blood." 



"(19) Particular studies of the blood-corpus :le3." 

 "(40) Prolonged studies of the physics of the body 



directed particularly to work out the history of the force 



generated in blood oxidation." 



OUR BOOK SHELF 



The Patentee's Manual. By James Johnson and J. 

 Henry Johnson. Fourth Edition. (London : Long- 

 mans and Co., 1879.) 



The law relating to letters-patent for inventions, as at 

 present administered, has been the growth of one short 

 sentence in a declaratory statute passed in the twenty-first 

 year of the reign of James \. (a.d. 1623), by which the 

 Crown was restrained from making extravagant or 

 oppressive grants of monopolies. The history or details 

 of patent cases may often form an interesting subject of 

 inquiry for the scientific reader; for although men of 

 the highest intellect may be content with the discovery of 

 general laws, and may leave their useful application and 

 development to the crowd of humbler followers whose 

 only power consists in the exercise of mechanical inge- 

 nuity, yet it cannot be denied that the successive steps 

 which have been made in the steam-engine, in the electric 

 telegraph, in machinery for spinning, weaving, or sewing, 

 for manufacturing paper, or for printing a newspaper, may 

 each in turn afford matter of considerable interest to a 

 philosopher whose imagination is wearied with an endea- 

 vour to trace the fantastic excursions of a molecule, or to 

 carry his dynamical laws into new and unexplored 

 regions. 



A book which shows the manner in which the property 

 in inventions is dealt with in our Courts, and which, in 

 order to accomplish its object, must of necessity review 

 the various cases in an historical and logical order, 

 affords, in a small compass, an epitome of much valuable 

 learning. It is remarkable that the first patent case of 

 any importance involved the validity of Arkvvright's 

 invention of machinery for drawing out and spinning 

 cotton (a.d. 1785), while the second occurred ten years 

 later, and related to the.invention of the separate condenser 

 «<: o ctpam-engine by James Watt. Since that period a 

 number of distmct steps in lUc useful appiii,ation of pkyciral 

 or mechanical laws have successively passed the ordeal of 

 judicial inquiry, and those who take up the volume before 

 us will find a reference to such matters as Wheatstone's 

 telegraph, the hot blast for smelting iron, the interlocking 

 of railway points and signals, the operation of currents 

 of air between the grinding surfaces of mill-stones, the 

 combing of wool, the laying of submarine telegraph- 

 wires, &c., and so on in a list which appears almost 

 interminable. 



But although the variety of subject-matter may be 

 great, the principles which govern the cases are few and 

 easily comprehended, and, in reading the statements of 

 principles laid down by Chief Justice Tindal and other 

 judges who have moulded our patent law into a coherent 

 form, the thought may arise that the purely scientific 

 writer who is composing his manual for the use of students 

 might with advantage borrow something of power of style 

 and of clear logical exposition from the lawyer, who is 

 popularly believed to be tied down and hampered by the 

 jargon of technical phraseology. 



The book now under notice has already passed through 

 three editions, and the authors have enlarged it by the 

 interpolation of recent cases, as well as by the addition of 

 new chapters. It is not within the scope of this journal 

 to examine such a treatise from a strictly legal point of 

 view, but we should describe it as exhibiting abundant 

 evidence of being the work of writers who are practically 

 engaged in professional pursuits. One important appendix 



consists of a digest of the patent laws in force in foreign 

 countries, and in the body of the work there is a chapter 

 on the ''oppositions to the grant of patents," which 

 suggests many melancholy thoughts to the sanguine 

 inventor, and leads one to hope that some improvement 

 of the enactment of 1852 will be conceded at an early 

 period. In conclusion we have only to say that the book 

 has fairly earned the circulation which has carried it to a 

 fourth edition. 



T. M. G. 



A Manual of the Carbon Process of Photography, S^c. 

 By Dr. Paul E. Liesegang. Translated from the 

 German by R. B. Marston. With Illustrations. 

 (London : Sampson Low, Marston, Searle, and Riving- 

 ton.) 



When, forty years ago, Mungo Ponton discovered that a 

 sheet of paper, moistened with a solution of potassium 

 dichromate, became darker when exposed to the rays of 

 the sun, he made the first of a series of experiments 

 which have led to the discovery of a method of rendering 

 photographic pictures as permanent as engravings made 

 in printing ink, though the completion of the work to a 

 point at which it could fairly be said to be capable of 

 competing with the well-known silver chloride print was 

 not made till nearly thirty years afterwards, when Swan, 

 by an admirable series of inventions, made it a practical 

 means of producing prints. 



In the history of the long struggle with nature which 

 has produced so great a result ever}^ Englishman has 

 reason to be proud, for it may be fairly said that 

 the world owes the process from first to last to 

 English workers. The process is now worked on 

 an immense scale in this country by the Autotype 

 Company and others, while another branch of the 

 same stem has developed into the well-known Woodbury- 

 type system of press-printing. Notwithstanding, how- 

 ever, the success of the process in its original home, 

 we are somewhat deficient in connected accounts of 

 it, most of the English publications on the matter 

 being, like the autotype manual, confined to working 

 details of the methods in use. We therefore welcome Dr. 

 Liesegang' s work as attempting something more than 

 this, and presenting what is really a most interesting 

 account of the whole subject, interesting, indeed, to any 

 one who has a taste for well- written scientific technology, 

 and apart from its value as a manual for actual working 

 details. In one respect, indeed, the carbon process has 

 all through been singularly fortunate. It seems, from the 

 first, to have fallen into competent scientific hands, and 

 to have escaped the dreary round of mess and muddle 

 experimenting which is so characteristic of the history 

 of the collodion negative processes, and which reminds one 

 of nothing so strongly as of the story ascribing the inven- 

 tion of a certain process for the purification of sewage to its 

 inventor going into a laboratory and taking down bottles 

 at random, to the number of some half dozen, adding 

 their contents to a sample of sewage, and patenting the 

 mixture. From this misfortune the carbon process has 

 been free, and Dr. Liesegang has been able to make its 

 history instructive and interesting ; he has given clear 

 and precise accounts of the processes in use, and we note 

 that he has kept well up with the latest improvements, 

 while the illustrations are well and clearly cut. The popu- 

 larity of the work in Germany has caused no less than 

 six editions to be demanded. 



It would be unfair to close this notice without a word 

 of praise to the translator, who, in a modest note, states 

 that his share of the work was done in leisure hours. 

 We can only wish that he will continue, as he has begun, 

 to introduce sterling foreign technical works to the public 

 in as vigorous and correct English as that in which he 

 i has dressed Dr. Liesegang's little book. 



R. J. F. 



