Januaet 14, 1921] 



SCIENCE 



47 



Union, etc.] during, the Roeky Mountain revolu- 

 tion ("Elements of Geology"). 



The reviewer therefore does not hesitate to 

 state that to him the evidence relating to the 

 field relations and stratigraphy, the orogeny 

 and paleogeography, and the invertebrate and 

 vertebrate fossils of the Montana series and 

 the Fox Hills and Lance formations is now 

 well enough in hand to conclude that all are 

 unmistakably of Mesozoic time. Furthermore, 

 as the Lance and Fort Union are continuous 

 formations, have wholly archaic mammal 

 faunas, and are broken by a period of orogeny 

 and lack of deposition from the succeeding 

 Eocene deposits with their wholly different 

 and modernized mammal faunas, the line sep- 

 arating the Mesozoic from the Cenozoic ap- 

 parently lies between the Fort Union and the 

 Wasatch, and not between the Fox Hills and 

 the Lance. From this conclusion the paleo- 

 botanists vrill of course dissent, but we have 

 now come to the parting of the ways. Our 

 floral brethren will continue to say that the 

 Cenozoic begins with the Lance, but the 

 dominating faunal evidence of the inverte- 

 brates and vertebrates, backed as it is by the 

 field relations and the two movements of the 

 Laramide revolution, binds invertebrate pa- 

 leontologists and geologists together in the 

 conviction that the Lance and the Fort Union 

 are of Mesozoic time. The U. S. Geological 

 Survey should now reverse its former con- 

 clusion and adapt itself to the fuller evidence. 



Charles Schuchert 

 Tale University 



SPECIAL ARTICLES 



AN ADJUSTABLE EMBOUCHUER 



The device shown in Fig. 1 was designed 



to evoke a definite note, fundamental or over- 

 tone, from cylindrical tubes, closed at one end 

 or open at both. It consists of a brass tube P, 

 pinched down at cc', so as to form a crevice 

 2 or 3 cm. long and not much more than i mm. 

 broad. From this issues a lamina of air 

 striking the strip of thin brass ss' about 5 mm. 

 broad. The strip ss' which is always to lie in 

 plane of the lamina, is on guides gg' of thick 

 copper wire, bent at right angles, as shown, 

 and soldered to the ears of the crevice cc. 

 In proportion as a higher or lower note is to 

 be evoked, ss' is placed nearer cc' or removed 

 from it; for the nearer ss' is to cc' the higher 

 the mean pitch of the sifiling. For high over- 

 tones the adjustment is rather delicate and 

 should be made (preferably) with a microm- 

 eter. In Fig. 1, ss' slides with slight friction 

 and is moved by the fingers. In use, the ap- 

 paratus is placed across the end of the pipe 

 with the plane gcc'g' normal to the axis. The 

 particular note wanted is obtained by cor- 

 rectly setting ss', which oi)eration sometimes 

 requires patience. The best results are ob- 

 tained with pipes of the one-foot octave, and 

 of a diameter less than twice the width cc', 

 pipes of about equal width with cc' being 

 most satisfactory. From inch gas pipe, two 

 feet long, a whole series of overtones may be 

 evoked in succession. With a less exacting 

 demand for an immediate response, clear 

 notes may be obtained from a great variety 

 of vessels. Thus bottles, deep tumblers and 

 beakers, flat jars (like sardine boxes), trim- 

 cated cones, thistle tubes and even thimbles 

 respond, often very loudly. 



Very disconcerting sounds are often ob- 

 tained. Thus, for a wide-mouthed cylindrical 

 jar, 3" in diameter and 6" high, tapering 



