llfl 



. IH:.MI>TUY. 



fees the explosive jra* thus creating a sudden 

 ipenston o/TuwhCh form ibTpfium down 

 Mite. The second upstroke in UM cylinder ei : 



Imm* tiMttpeAMffpses through * pi|>e opened 



.... .-..,.: K, v 



..,-..-, ' ..in, -. 

 .' ..... :- ' " " :> 



from the occupants of the vehicle. The 

 motor is the kind most 



m 



ployed. To Hart thr motor a little crank miM 

 be tamed half a down times, tometimt* M 

 m half a minute, to enable the machine to 

 ma. Thb constitutes the only 



to it 



..in I. and require* no safety 

 When a motor is stopped or 

 hut off it i* di-ad. and there can be no effort 

 on its part until half a dozen turns of the crank 

 have socked in a mixture of gas and air to begin 

 or ft again a series of explosions in the cylinders. 

 The efforts that ar being made by inventors to 

 do away with the disadvantage mentioned may 

 bt appreciated, when it is said that in the large 

 motors of this kind for use in mills and like 

 heavy establishment* the engines of 100 horse 

 power obtain the start by toe use of several 

 smaller engines. Of coarse it would be fut il- to 

 attempt to start bv hand an engine of 100 horse 

 power. The smallest of these engines is not too 

 large to be started by hand. This smallest en- 

 gine. as noon as it has got its own power, in t urn 

 sets the second one, and that starts the main 

 machine. 



Hithmo it has been necessary to carry on a 

 journey in one of these horseless carriages at 

 least a barrel of water for cooling the cylinders. 

 A new device, by which a smaller quantity will 

 be sufficient, consists of an arrangement l.y 

 which the water used to cool the cylinders is re- 



soon as it is used, and then 

 to play its part over and over again. The 

 fuel used is not worth making any 



effort to reduce, as it is only a pint of petroleum 

 an boor to each bores power. Three horse 

 powers was the capacity of the winner at the last 

 Paris race. The most successful of the 1 



far for doing awar with the inconvenience 

 in tailing the machine is a contrivance, now 

 popular in Paris, of a gearing by which, when 

 the carriage is stopped for a few minutes, a 



II wheel takes ih- |,*.T and continues the 

 engine in motion, hut with the power not applied 

 to the wheels of the wagon. 



Two large firms in Paris are very busy sup- 

 plying UM demand for horseless carriages. One 

 make* carriage, with wooden spokes, while th- 

 oth-r pr.lucee a vehicle with the steel spokes 

 thai rhararteriM the bicycle. It was one of the 

 latter, carrying 4 persons, that won the special 

 prixe in the great French race. The 750-mile 

 Journey was 



A factory for 

 rmges has b, 

 bland, near Astoria, 



CHF.MMTET. Chemical Thoory.-Prof. 

 Raphael Mendols, opening the chemical section 

 of the British Association with an address on 

 the progress of chemical science, remarked that 

 the recognition of the qnanti valency of carbon 

 by Kekule in 1856 was the beginning of the 



lopment <>f chemical science. The 

 concent ion ol thr valency of the atoms was 

 bfoacoed by Prankknd .-md shortly 



after that time the course of <li 

 concentrate itself in two channels; one follow- 

 ing the physical side, and the other carrying 

 "the : in- from the ralenOJ 



doctrine and its extension to the structure of 

 chemical molecule-." The two channels are at 

 present fairly parallel and not far apart. \Vc 

 nave one class of worker- dealing with the phys- 

 ics of mutter in relation to general obemicaJ 

 properties, and another Ha>s of investigators 

 concerning themselves with the special proper- 

 ties of individual compounds and classes of com- 

 pounds with atomic idio-;. 

 ers of one class are differentiating, while their 

 colleagues are integrating. Moth meth. 

 necessary for the development of the s< 

 and there is no antagonism, l.ut co-i.pi-niti.in. 



The success attending the application of the 

 doctrine of valency to the compounds of . 

 has helped its extension to all compounds formed 

 by other elements, and the student of the pres- 

 ent day is taught to use structural fornn 

 the A BC of his science. The doctrine in its 

 present state is empirical, but we can hardly 

 doubt that a physical reality underlies it. Then 

 is something to be reckoned with besides val- 

 ency. The great desideratum of modern chem- 

 istry is a physical or mechanical interpretation 

 of the combining capacities of the atoms. The 

 services of the doctrine of Valency, however, in 

 the construction of rational formulas, especially 

 within the limits of isomerism, have been incal- 

 culable. The doctrine underwent a prolific de- 

 velopment through the introdud ion of t he stereo- 

 chemical hypothesis in 1874; and .renewed vi- 

 tality was given it by the conceptions of tautom- 

 erism and deomotropy, formulated by Laar in 

 1885, and by Paul Jacobson in 1887. A more re- 

 cent development of structural chemist ry is the 

 conception of certain ideal complexes of atoms 

 which we consider to be the nucleus or type 

 from which the com|H>und of known constitution 

 is derived. In some cases these types have been 

 shown to be capable of existence ; in other cases 

 still ideal. The parent compound \r.i< 

 sometimes been known before its derivative, as 

 in the case of ammonia and the organic amines 

 and amides: and in other instances the deriva- 

 tives were obtained before the type was isolated, 

 a* in the case of the hydra/incs. which were 

 characteri/ed in 1875, and the hydra/ 

 (Kiiinds. which have been known since 1868, 

 while hvdrazine itself was only first obtained in 

 1887. This theory is also capable of almo-t in- 

 definite extension. The present position of 

 structural chemistry may n<- rammM up in the 

 statement that we have gained an enormous in- 

 Mi:ht into the anatomy of molecules, while our 

 knowledge of their physiology isjis yet in a rndi- 

 iry condition. 



The theory i* sustained bv I)r. T. L. Phipson 

 that H. here was originally of ni 1 



only, and the free oxygen which now forms part 

 of the air we breathe is entirely the product of 

 plant life extending over countless ages not 

 that plants were the creators of oxygen, but 

 that they were the means by which Nature has 

 placed free oxygen gas in the atmosphere of the 



