July 7, 1904] 



NA TURE 



233 



Its sediments of the thoroughly characteristic pottery of 

 the youngest (the iron culture) of the south tumulus. 



(4) After this, and apparently contemporaneous with the 

 founding of Anau, irrigation began through which the plain 

 was raised 15 feet, bringing it to its present condition, in 

 which the north tumulus stands embedded to a depth of 

 27 feet, the south tumulus to the depth of 22 feet, and 

 Anau to i; feet. 



EFFECT OF SOUND ON WATER JETS.* 



'TTHE structure of water jets was first investigated by 

 M. Savart, who in 1833 published a series of beautiful 

 papers in the Aniiales de Chimie et de Physique. Since 

 then it has received the attention of many experimenters, 

 notably M. Plateau and Prof. Magnus, while of later years 



connecting ligament, which separates and forms a smaller 

 drop (Fig. i). If the jet is falling freely, and subject only 

 to accidental tremors and disturbances, the formation of 

 drops is by no means regular, and the sizes and shapes of 

 the drops vary much. If a vibrating tuning fork be held 

 in contact with the stand, and if the pressure of water and 

 the diameter of the orifice be suitable, the jet will appear 

 like a vibrating string, a succession of nodes and loops 

 being formed. The effect of the tuning fork is to render 

 the separation of the drops regular, a drop being cast off 

 with each vibration of the fork. If the jet be falling 

 \ertically, as the drop leaves the end of the clear column 

 it is extended in a horizontal direction, but as it falls it 

 oscillates about the spherical form, being alternately 

 elongated and compressed under the action of the surface 

 tension of the liquid (Fig. 2). 



Prof. Magnus explained that the wavy appearance of the 



jet under the action of the tuning 



1 fork was due to all the drops which 



arrive at any given point of space 



being in the same phase ; at the 



_ middle of a swelling they are most 



elongated horizontally, and midway 



, I between the broadest portions of two 



consecutive swellings they are most 



elongated vertically. 



^ These remarks apply to a jet of 



« water about 2 mm. in diameter. If 



the diameter of the jet be much less 



Q than I mm., swellings are not pro- 



' duced in it. The effect of a tuning 



fork is to render the drops practically 



* equidistant and uniform in size 



• 9 (Fig. 3). If a fine jet be projected 



upwards (Fig. 4) it will be seen to 



consist of irregular drops, while the 



effect of a tuning fork upon it is 



® often to cause it to break up into 



several distinct streams (Fig. 5). 



THE POISON OF THE 

 B.iNDED KRAIT.'^ 



Jl 



Fit;. 1. — Some Irstantaneous Photographs of Water Ji 



our knowledge of the subject has been much added to 

 by the observations and mathematical researches of Lord 

 Rayleigh. The older experimenters had to content them- 

 selves with observing the jet through a revolving disc with 

 radial slots, but by means of an electric spark and rapid 

 plates we can now secure photographs of the jet at any 

 desired instant. The eye shows us that a jet of water 

 consists of two parts, (i) a clear column, and (2) a troubled 

 portion. The spark reveals to us that the troubled portion, 

 though apparently continuous, is really a succession of 

 drops, which move too rapidly for the eye to perceive them 

 as such while under continuous illumination. 



Towards the lower part of the clear column of water 

 the jet presents alternate swellings and contractions, and 

 at the very extremity a drop is cast off, leaving behind a 



1 "The Structure of Water lets, and the Effect of Sound thereon." 

 By Philip E. Belas. Roval Colleg- of Sciencs. Dublin. With photographs. 

 Abstract of paper read before the Royal Dublin Society on March 15. 



NO. 1810, VOL. 70] 



'HERE is an unbounded field in 



India for the study of the 



venoms of the many species of 



o poisonous snakes met with in that 



Q* country, and the Government of 



India has been well advised to devote 



to this subject certain of its scientific 



• memoirs now being issued from time 



^ to time. Captain Lamb, I. M.S., the 



author of the one under review, has 



' already done good work in this 



" branch of research. 



The venoms of various snakes, 



C though all composed of the same 



" class of chemical substances (co- 



agulable proteids and proteoses) in 



's. varying proportion, differ markedly 



in their physiological actions, and it 



can be shown not only physiologically, but also by certain 



test-tube reactions, that the proteids and proteoses are 



different in the different venoms. 



Thus the blood serum of an animal that has been mjected 

 with cobra venom causes a precipitate when mixed with 

 an aqueous solution of cobra venom, but has no such action 

 when mixed with a solution of the venom of the Australian 

 tiger snake. As regards the venom of the banded krait 

 {Bungams fasciatus), with which this memoir _ deals, 

 Captain Lamb's researches show that cases of poisoning 

 may be divided into three classes : — (i) those in which after 

 a large dose rapid death follows from the occurrence of 

 extensive blood coagulation in the blood vessels ; (2) those 

 which are fatal after two or three days, and present acute 



1 Scientific Memoirs by Officers of the Medical and Sanitary Depart- 

 ments of the Government of India. No. 7, 1904. " Some Observations on 

 the Poison of the Banded Krait (Bunfanis /axciatm)." By Captain 

 George Lamb, M.D., I. M.S. (Calcutta: Government Printing Office, 1904 



