NATURE 



[March 27, 1902 



would not possess, while at the same time it may 

 be useful in making accurate tests on small specimens ; 

 such tests the committee is prepared to undertake, 

 though it fully recognises the desirability of erecting a 

 large machine as soon as funds will permit. The usual 

 accessories for torsion and bending tests are fitted ; 

 there is also a simple autographic gear. 



The pressure pumps for the gauge-testing work sup- 

 plied by Messrs. Schaffer and Budenberg were placed 

 temporarily in an adjoining room. These are two in 

 number ; one is arranged to test simultaneously ten or 

 twelve gauges up to a pressure of 600 lbs. to the square 

 inch ; the pi-essure is applied by a force pump and a 

 screw plunger. In the other, a pressure of twelve tons to 

 the square inch can be obtained easily. The indicator- 

 testing apparatus given by Messrs. Willans and Robinson 

 has not yet arrived. In the engine-room the 75 kilowatt 

 Parsons' turbine was running, and proved an attraction 

 to many visitors. The normal voltage of this machine 

 is about 105. The room also contains a 10 kilowatt 

 dynamo by Thomas Parker and Co., driven by a Crossley 

 gas-engine and a motor generator set also by Parkers. 

 By means of regulating resistances, the dynamo of this 

 set can be made to run at voltages between 10 and 60. 

 There are three storage batteries, each of about 55 chloride 

 cells, in the Laboratory, and by running the generator in 

 series witli the main dynamo each of these can be 

 charged. But in experimental work the cells are likely 

 to be unequally used ; the generator alone can then be 

 used to charge groups of cells which require special 

 treatment. 



With regard to the physical part of the Laboratory, it 

 must be remembered that the staff has only been in the 

 building for a very short period, the electrical rooms 

 were not ready for occupation until about ten days before 

 the opening, and, further, that the funds at the disposal 

 of the committee have sufficed to purchase only a limited 

 equipment. The aim of the director has been to com- 

 plete as far as possible the apparatus required for experi- 

 ments which it is hoped to undertake at once ; no 

 apparatus has been bought without an express and 

 immediate object in view. The thermometric depart- 

 ment is perhaps the most completely fitted. The main 

 laboratory has been divided into two by a partition of 

 soft brick and glass. On the one side are the various 

 furnaces and heating appliances, on the other the 

 measuring instruments which it is desired to keep at a 

 uniform temperature or to protect from fumes. The 

 brick can easily be drilled to allow the passage of wires, 

 tubes, &c.; through the glass the observer can see what 

 is happening on the other side of the partition. Appliances 

 were shown for standardising thermometric instruments 

 from the temperature of liquid air up to 1 000^0. or 1200'C. 

 This laboratory is in the charge of Dr. Marker, who has 

 shown much ability in arranging the various appliances. 



For the liquid air there is a Hampson liquefier attached 

 to a Brotherhood compressor, which is driven by a 5 h.p. 

 motor by Laurence Scott and Co., of Norwich. For 

 boiling-point observations and for calibration, the 

 standard apparatus as used at Sevres has been fitted. 

 For temperatures between boiling point and 200' C. to 

 250'' Can oil bath has been constructed. This consists of 

 a wide U-tube of copper having a junction across the 

 upper part of the U. In the one limb is a stirrer driven 

 by a small motor, in the other the thermometers are 

 placed ; thus a continuous stream of oi) is driven rapidly 

 past the thermometers. The whole is jacketed and 

 heated by gas, and careful observations have shown that 

 the temperature over the whole of the vertical column is 

 remarkably uniform. 



For temperatures up to about 600' C. there is a similar 

 bath of iron containing a mixture in equal parts of the 

 nitrates of potassium and sodium. 



The higher temperatures up to nearly 1200' C. arc ob- 



NO. 1 69 I, VOL. 65] 



taincd in an electric oven similar to that used by Messrs. 

 Holborn and Day at the Reichsanstalt, and the director is 

 indebted to President Kohlrausch for kind assistance in 

 procuring the materials for this. The oven, which was 

 the gift of Sir Andrew Noble, consists of a series of tubes 

 of porcelain and fireclay carefully lagged with asbestos ; 

 round the innermost tube a nickel wire is coiled ; this is 

 heated by a current, and a remarkably steady and uniform 

 condition of temperature is obtained ; the regulation of 

 the temperature is easy, and there are no fumes to 

 contend with. 



For success with the oven it is necessary that the 

 electric supply should be uniform ; a special battery of 56 

 cells has therefore been installed. This has been 

 arranged in four groups of 14 cells each, and by means of 

 a specially devised switchboard these can be combined in 

 various ways to give the required current and voltage. 

 This battery was the gift of Sir Andrew Noble, to whom 

 also is due the gas thermometer which at present forms 

 the standard of reference. For secondary standards, 

 mercury thermometers will be used up to 250' or possibly 

 rather higher ; above this platinum thermometers, or 

 possibly thermopiles, will be adopted. Among the ex- 

 hibits were three thermal-junctions most carefully 

 standardised by Prof. Holborn, which will form a link 

 between the Laboratory and the Reichsanstalt ; there was 

 also a platinum thermometer in a quartz tube, very kindly 

 given' by Mr. \V. A. Shenstone. .A. cathetometer set up 

 temporarily against the wall attracted special notice. 



At no great distance from the thermometric laboratory 

 is the mercury pressure gauge. A glass column some 

 fifty feet high has been fixed to the wall of the labora- 

 tory ; alongside this is a steel scale, di\ided into 

 millimetres, pounds per square inch, kilogrammes per 

 square centimetre, and feet of water : thus gauges up to 

 a pressure of 250 lbs. to the inch can be tested 

 directly against the column. A lift erected close to the 

 column enables the observer to read the height of the 

 mercury. The pressure is applied by means of com- 

 pressed air contained in a bottle connected both to the 

 gauge and the mercury column. The bottle will be 

 filled from the Brotherhood compressor which works the 

 air liquefier. For standardising gauges between 250 

 and 400 lbs. pressure, a loaded piston apparatus — a gift 

 from -Messrs. Willans and Robinson — will be available ; 

 for pressures above this, apparatus has to be constructed. 



The metallurgical department is housed in the old 

 kitchen, in which there was an interesting exhibition of 

 photographs of metallic sections and cooling curves, lent 

 by .Sir William Roberts-.Austen. The apparatus for in- 

 vestigating cooling curves has yet to be bought, but a 

 beautiful photomicrographical outfit by Zeiss was shown 

 by Dr. Carpenter, who exhibited to a number of the 

 guests the section of a steel rail magnified four hundred 

 times ; the pearlite and ferrite structures were clearly 

 visible ; the rail had been rolled cold and the grains were 

 elongated by the rolling. The projection apparatus is very 

 complete ; the arrangements for cutting, grinding and 

 polishing the sections are also ready ; the polishing 

 apparatus has been specially designed by Mr. J. E. 

 Stead, and the laboratory is prepared to undertake the 

 microscopic examination of sections for the railway com- 

 panies or other users. 



A room adjoining the microscope is arranged for 

 metrology, and here were set up a dividing engine 

 by the Societe Gdnevoise pour la Construction 

 d' Instruments de Physique. This instrument was 

 given by Sir Andrew Noble, and is a copy of that 

 in use at the Bureau International, but without the 

 automatic mechanism — this, however, can be added if 

 funds permit. It will divide lengths of i metre or 

 less. The room also contained a Whitworth measuring 

 machine, a set of standard gauges, surface plates, &c. 

 .\ set of screw gauges had most kindly been lent by 



