•134 



SCIENCE. 



[Vol. XV. No. 368 



,as celestial bodies were moving as storm-centres drift, east- 

 ward. 



Would it not be of interest to learn from correspondents how 

 far the gay deceiver was seen ? It was so exceptionally striking, 

 that no person favorably situated could have failed to observe 

 it, and no one could but be impressed by the beauty of the 

 .unusual event. L- W. Ledtaed. 



Cazenovia, N.T., Feb. 18. 



The Fiske Range-Finder. 



With reference to the note of Lieut. Casey in your issue of 

 Jan. 31, 1890, calling attention to an apparent hiatus in the 

 theory of my range-finder, permit me to say that Lieut. Casey is 

 «ntirely correct in all his statements and deductions, but that the 

 instrument does in reality make an autoinatic correction which 

 has not yet "been publicly described. There are a number of 

 ways of accomplishing it ; but it does not seem advisable to de- 

 scribe any of them yet, in view of patent applications now pend- 

 ing. Bradley A. Fiske, U.S.N. 



Norfolk, Va., Feb. 12. 



Answers. 



49. Influenza. — In reply to the query in Science of Jan. 

 17, "Has epidemic influenza been known to cross the equa- 

 torial line?" I beg to append the following: The epidemic of 

 1836-37, which originated probably in Russia, -'also spread to 

 the southern hemisphere, and prevailed at Sydney and the Cape 

 ■of Good Hope at the same time that it visited the north of 

 Europe" (C2jclopcedia of 31edicine, Von Ziemssen, ii. p. 533). 



Harvey B. B ashore. 



"West Fail-view, Penn., Feb. 17. 



INDUSTRIAL NOTES. 

 Improvements in Electric IVIotors. 



In Science, o^ Dec. 18, the Crocker -"Wheeler electric motor, 

 -as applied to pumps and fans, was illustrated and described. 

 The accompanying engravings show the improved motor as now 

 manufactured by the Crocker-"Wheeler Company, and also an 

 improved starting-switch and device for adjusting the speed 

 and power. 



The improved motors contain all the features which, during 

 several years' experience in the manufacture and operation of a 

 large number of successful motors, have been found to increase 

 their strength, economical use of current, general appearance, 

 and their convenience for starting, stopping, and regulating. 

 The construction has been improved to permit the use of wire 

 on the armature two sizes larger than has been possible before, 

 therefore making the winding much less liable to breakage, 

 .and enabling it to carry more current without heating. The 

 ^-horse-power motor is made to run at a practically steady speed, 

 even with the most sudden and heavy changes of load. The 

 base is made extra heavy, with the centre of gravity low, to 

 add to the steadiness and solidity of the machine. The bear- 

 ings are made of the best babbitt metal, the same as on large 

 steam-engines and other iirst-class machinery, ' this being a 

 new feature in small motors. 



The efficiency of these machines, or the amount of power 

 that they will furnish from the consumption of a given amount 

 of electricity, has 'been materially increased. The direction of 

 rotation is made reversible by simply changing the brush- 

 holders, and considerable advance is made in the finish of the 

 machine, the best workmanshiij being bestowed upon every 

 part. 



"With the adjusting- switch in the position shown in Fig. 3, 

 these motors run at full speed (1,900 revolutions per minute), 

 and in the position shown in Fig. 3 they run at about half 

 -speed. The windings are so proportioned that in either case the 

 pi-oper current flows through, and runs the motors at the 

 resijective speeds with high efidciency. 



The new "K" winding on these machines takes the place of 

 the lamp frequently used on the top of other motors to vary 

 the speed. It is a radical improvement in this respect, saving 

 the current usually wasted on the lamp, and giving a means 

 of instantly changing the motor's speed by turning the knob 



without the use of resistance-boxes or the trouble of unscrew- 

 ing and removing a lamp. The starting-switch is shown in 

 Fig. 4. 



The arrangement is adapted to running fans, pumps, and all 

 kinds of machinery that are not subject to extreme variations, 

 and is superior for these purposes on account of the facilities it 



offers of changing the speed. For work which is variable and 

 sometimes thrown off entirely, as in the case of buff-wheels, 

 lathes, etc. , the constant sneed motors are preferable, because 

 they maintain steady speed at all times. 



The Springfield Industrial Drawing-Kit and Drawing-Model 

 Support. 



E-FERY di-aughtsman finds a di-awing-board, a T-square, and 

 one or more triangles as essential to his work as are the scale of 

 inches and tlie compasses, and every pupil in mechanical draw- 

 ing requires a similar outfit. The Springfield industrial di-awing 

 kit, shown in the illustrations, is intended for use in grammar 

 and high schools, the family, the office, and the shop. 



The set (Fig. 1) consists of a board about ten by twelve inches, 



