NA TURE 



[May 3, 1906 



suffered great damage by the earthquake on April 18. 

 A massive gateway of stone at the main entrance to the 

 University grounds is now a ruin, and the great dragons 

 which surmounted it lie broken to pieces on the ground. 

 An immense memorial arch has been wrecked, and a fine 

 marble memorial to Henry Lathrop, Mrs. Stanford's 

 brother, lias been demolished. The museum has been 

 seriously damaged, the whole roof of the art gallery having 

 fallen in, and part of the roof of the other wing. The 

 entire centre of the building devoted lo the department of 

 chemistry is a wreck. The gymnasium, just completed 

 and never used, is an absolute ruin, and another large new 

 building, the library, also just completed and about to 

 be dedicated, is in the same condition. The building de- 

 voted to zoology and physiologv is not much damaged. 

 I he president of the Universitv, Dr. D. S. Jordan, who 

 was at home at the time of the earthquake, believes that 

 the shock of April 18 was not onlv one of the severest, 

 but also one of the longest duration on record. The Times 

 correspondent learns also that the narrow-gauge railway 

 to Santa Cruz has been so badlv damaged that it will be 

 months before trains can again be run. There are many 

 tunnels on this line, and in various instances these tunnels, 

 which formerly were straight lines, are now corkscrew- 

 shaped. .\\ San Jose a flower garden was turned into a 

 lake of mud from which a dozen gevsers burst into activity 

 after the earthquake. 



The current number of the Universitv Revic-iU contains 

 an inspiring article on " Science and the'Public " by Major 

 Ronald Ross, F.R.S., professor of tropical medicine in the 

 University of Liverpool. Insistence is laid on the fact that 

 science is almost exclusively the work of individuals, and 

 that, though willing enough to benefit bv the discoveries 

 and inventions of men of science, the public is in no sense 

 imbued with the scientific spirit. Instead of cultivating 

 (he absolutely impartial judgment demanded by science, the 

 public encourages the habit of mind eulogised by Tenny- 

 son, ■■ believing where we cannot prove," and forgets there 

 is nothing meritorious in such conduct, but much that is 

 the reverse. The essay proceeds to show that to this 

 willingness to ignore science and scientific methods mav be 

 traced the credulity of the public which leads it to sub- 

 sidise quack medicine, to ignore beneficent discoveries like 

 that of Jenner, to hamper scientific research bv unintelli- 

 !jent anti-vivisection societies, and generally to proclaim 

 Its adherence to the policy of "muddling through." An 

 instance is given by Major Ross from his own experience 

 which shows how slightly as vet the mass of mankind has 

 been influenced by scientific methods. More than seven 

 years ago it was demonstrated that malaria is conveyed 

 from man to man by a group of gnats, and several obvious 

 and practicable modes of prevention were suggested in 

 consequence of the discovery. But when these 'measures 

 were urged upon the public and governments of our tropical 

 colonies, the so-called educated white people scoffed at the 

 whole discovery, without troubling to ascertain the facts 

 and the governments, with the exception of a few, took 

 no action which could for a moment be called adequate. 

 I he magnitude of the offence mav be gathered when it is 

 remembered that half the people in the tropics suffer from 

 the disease every year ; but in view of recent events it is 

 easy to see that the world will be dominated eventually 

 more and more by the disciplined and scientific peoples 

 and those nations which reject science will be set aside. 



SOCIETIES AND ACADEMIES. 



I-ONDON. 



Royal Society, January 25.— "An Electrical Measuring 

 Machine." By Dr. P. E. Shaw. Communicated by 

 Prof. J. H. Poynting, F.R.S. 



The principle of the measuring machines in general use 

 is that one face of the gauge rests against one jaw, fixed, 

 of the machine, whilst the other jaw is moved forward by 

 a screw until it touches the other face. These machines 

 may be called mechanical-touch machines in contradistinc- 

 hon to the new machine called the electric-touch machine. 

 This depends on the same general principle as the electric 

 micrometer used by the author in several researches. 



Objections to the mechanical-touch methods are :— 

 NO. 1905, VOL. 74] 



(i) they involve strain in the machine of a much larger 

 order than in the electric method ; (2) they are less sensi- 

 tive ; (3) it is impossible to measure between point and 

 point. To measure between points or rounded points is 

 essential in accurate metrology, especially for gauges with 

 flat ends ; for when each jaw has a flat face and each 

 end of the gauge has also a flat face, each of these four 

 faces having errors in planeness and parallelism, the re- 

 sulting measurements must be erroneous. If, however, 

 measurement be taken between small spheres on the screw 

 ends, no assumptions as to planeness and parallelism are 

 made, and such errors vanish from the results. 



The electric measuring machine consists of (a) two head- 

 stocks containing micrometer screws ; (6) a table to carry 

 the gauge ; (c) a massive slide bed, on which run the head- 

 stocks and table. The gauge to be measured is clamped 

 on the table, and is set true with respect to the micro- 

 rneter screws by two rotations and two translations pro- 

 vided in the table. This adjustment is made by special 

 electric-touch methods devised for the purpose. To make 

 a measurement of the gauge the left screw is brought 

 into electric contact (indicated by a telephone) with the 

 gauge ; then the right screw is brought into electric touch 

 with it, and when current passes through from one measur- 

 ing point to the other the two divided "heads on the micro- 

 meter screws are read. To turn the graduated head the 

 screw system is not actually touched by the hand, but is 

 worked by an outside hand-pulley and string. 



Special care is taken in the design of the machine to 

 avoid periodical screw error and backlash. 



A careful calibration by wave-lengths of several milli- 

 metres of the screws shows where they are specially 

 uniform, and therefore fit for use. 



Results are obtained for all kinds of gauges. For bar 

 gauges with flat ends, measurements taken at many places 

 reveal considerable variation in thickness, so that irregular 

 contour curves, roughly centred in the centre of the gauge 

 faces, can be drawn showing that the ends are far from 

 being plane or parallel. These errors in bar gauges have 

 not been previously pointed out or measured. The author 

 contends that all bar gauges should be measured by this 

 method and the errors registered, so that, even if the 

 errors are not corrected, by re-scraping or otherwise, they 

 will be known and allowed for. 



Cylindrical and spherical gauges are also tested ; these 

 are shown to be much more nearly perfect than bar gauges. 



A further use of the machine is in the measurernent of 

 non-conducting bodies, such as glass plates, the thickness 

 of which can be measured with great accuracy. 



Readings are taken with ease and certainty to i^25o,oooth 

 of an inch, and one-quarter of this can be obtained if 

 specially desired. 



March i. — " An Experimental Inquiry into the Factors 

 which determine the Growth and Activity of the Mammary 

 Glands." By Miss J. E. Lane-Claypon, D.Sc, and Prof. 

 E. H. Starling, F.R.S. 



So far as the authors' experiments go, they show that the 

 growth of the mammary glands during pregnancy is due 

 to the action of a specific chemical stimulus produced in 

 the fertilised ovum. The amount of this substance in- 

 creases with the growth of the fcetus, and is therefore 

 largest during the latter half of pregnancy. Lactation is 

 due to the removal of this substance, which must therefore 

 be regarded as exerting an inhibitory influence on the gland 

 cells, hindering their secretory activity and furthering their 

 growth. It is probable that the specific substance is 

 diffusible, and will withstand the boiling temperature. 



The authors do not, however, claim that these conclusions 

 are firmly established. A final decision can onlv be given 

 by a research carried on under more favourable conditions. 

 In fact, a farm is required where the authors could have 

 at their disposal 500 rabbits, and could arrange for a 

 plentiful supply each day of rabbits about the middle of 

 pregnancy. 



Zoological Society, April 10. — Mr. H. Druce, vice- 

 presiuent. in the chair. — The fresh-water fishes of the 

 island of Trinidad : C. Tate Regan. The author's remarks 

 were chiefly based on a collection made by Mr. Lechmere 

 Guppy, jun., and presented by him to the British Museum. 



