April 21, 1910] 



NATURE 



21 



(iriessmann, Knoblauch, Thomas, and others. As the 

 result of a careful weighing- of these various experi- 

 ments, the authors present the following formula con- 

 necting the total heat of one pound of dry saturated 

 steam with its temperature (Fahrenheit) : — 



H^IISO^ + O-- 45(t-2I2)-0'000550(f-2I2)*. 



The equation heretofore in use was H = 1082+0305^, 

 which may also be put in the more directly compar- 

 able form of 



H=ii47+o-305(f-2i2). 



It will be seen that there is a considerable differ- 

 ence in form between these two statements, although 

 as one is of the second degree and the other of the 

 first it is. not easy to tell at sight by how much they 

 would differ over the working range. The best way 

 of comparing theninis to set the figures in the old 

 steam tables side by side with those in the new. 

 This we have done for each increase of 50 lb. in the 

 pressure. The figures in brackets are those of the 

 old tables, as taken from such a standard book as 

 Perry's " Steam Engine," and the remaining figures 

 are those of the tables now published. 



It will be seen that at the ordinary steam-engine 

 pressures of 150 to 250 Ib./in.^*, there is very little 

 difference between the two sets of figures, but that 

 at lower pressures there is some variation, although 

 in no case is it extreme. On the other hand, many 

 calculations involve the estimation of differences of 

 heat content, and in those cases it is essential to allow 

 for any such corrections in the received steam tables. 

 It is, therefore, hardly too much, perhaps, to suggest 

 to those who have made important calculations with 

 the old tables that they should recalculate their results 

 on the basis of these' later fiures. 



Anyone reading carefully what the authors are 

 able to say in support of the figures they give must 

 concede that their researches have produced tables 

 based on what is probably the most accurate data 

 procurable at the present time. The theory of the 

 steam engine will be considerably aided thereby, and 

 one cannot but regret that there are no tables of equal 

 accuracy applicable to the working fluid in the internal- 

 combustion engine. 



We regret that the authors should have pre- 

 sented the bulk of their results in the unscientific 

 Fahrenheit scale. All who know the pitfalls which 

 beset the paths of students will agree that, of them 

 ill, the most common and dangerous is the elusive 

 NO. 21 12, VOL. 83] 



"32 " in the Fahrenheit scale. To have such a con- 

 stant is never of any use, and its avoidance is the 

 great merit of the centigrade scale. We should like 

 to see these tables published throughout in the scien- 

 tific temperature scale. 



The book contains two sheets of very useful curves, 

 which enable large numbers of simple problems to 

 be solved by mere inspection. .Among the illustra- 

 tions given we quote the following : — 



(a) A vessel of 4 cu. ft. capacity contains o'2 lb. of 

 water and 0-8 lb. steam. What is the pressure? 



(b) What is the entropy of i lb. of steam at 100 lb. 

 pressure and 450° F. ? 



(c) Steam of 140 lb. pressure, superheated 120° F., 

 expands adiabatically with a ratio of expansion of 6. 

 What are the pressure and quality at the end of 

 expansion ? 



(d) Steam at 100 lb. pressure, superheated 60° F., 

 expands in a nozzle to a pressure of 2 Ib./in.^. What 

 is its final velocity? 



(t) Steam in a throttling calorimeter with a pressure 

 of 17 lb. /in.-, and a temperature of 265° F. The 

 initial pressure of the steam was 100 lb. /in.-. \\'hat 

 was its initial quality? 



It w^ill be admitted that the ready facility with 

 w^hich such problems can be solved by two simple 

 sheets of curves is a great gain, and many workers 

 in science and engineering will be thankful for this 

 help. H. E. W1.MPERIS. 



SKAKE VENOMS. 

 Snake Venoms. An Investigation of Venomous 

 Snakes, with Special Reference to the Phenomena 

 of their Venoms. By Dr. Hideyo Noguchi. Pp. 

 xvii + 315. (Washington : Carnegie Institution of 

 Washington, 1909.) 



IT is now forty years since Fayrer and Weir Mitchell 

 laid the experimental foundations of knowledge of 

 the chemical characters and physiological actions of 

 snake venoms, their investigations being inspired 

 largely by the desire to combat the high annual death 

 rate from snake-bite. The study of snake venoms has, 

 however, obtained a greater interest since the publica- 

 tion, about fifteen years ago, of observations demon- 

 strating the possibility of producing a high degree of 

 immunity in animals and proving the antidotal pro- 

 perties of the serum of the immunised animals. These 

 phenomena in regard to snake venoms, having been 

 brought into line with similar phenomena in regard 

 to bacterial toxins especially, have been bound up with, 

 and have contributed largely to, the elucidation of the 

 problems of immunity which have in so many direc- 

 tions influenced modern medical thought. Hence there 

 has arisen in regard to snake venoms a literature of 

 high importance, and, from its involving scientific 

 investigators in many countries, a literature neces- 

 sarily extensiv^e and dispersed. 



.\s the author of this book states, there is at this 

 time, in the English language, no single work which 

 treats of the zoological, anatomical, physiological, and 

 pathological characteristics of venomous snakes tvith 

 special reference to the properties of their venoms. As 

 something more than a mere summary of the position 



