A glass enveloped Penning type cold cathode ionization gauge, having a latticed anode with three cells and a cathode with two sheets of titanium plate, was fabricated for trial use as a getter-ion pump.
The pumping speed was measured as a function of the anode voltage, the magnetic field strength, and the pressure. The speed at moderate operating conditions was about 1 liter per second. Existence of linearity between pressure and discharge current was ascertained. Hysteresis phenomena, i. e., the pump's memory of its previous conditions was observed in the measurement of pumping characteristics. An ultimate pressure of 10^-9 mmHg was obtainable without special difficulty.
Practical usefulness of such a small getter-ion pump was established in our laboratory. As an example of its application, processing of an ordingry thermionic tube on exhaust is shown.

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With the advent of getter-ion pumps, it seems worthwhile to examine its pumping behaviour and effect on the residual gases within glass-metal vacuum system.
A titanium getter-ion pump similar to the cold cathode “VacIon” type developed by Hall and the ultra-high vacuum mass spectrometer designed for the study of surface phenomena in ultra-high vacuum were chosen for this purpose.
Some pumping characteristics of a getter-ion pump and vacuum phenomena in bakeable glass-metal lsystam evacuated by getter-ion pump at various baking conditions have been investigated.

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Since the titanium getter pump was investigated by Prof. Herb in 1954, it has been recognized that it is a powerful tool to obtain “clean vacuum”.
In Japan, valuable improvements were done by the group associated under Prof. Kumagai (J. Vac. Soc. Japan 1 22, July 1958), subsequent work has followed in Japan Vacuum Engineering Co. Ltd., and applications have been found both in nuclear machines and in some industrial high vacuum instrument such as vacuum sintering furnaces, metal vapor coating units and small electron beam furnaces.
Many difficulties were experienced in manufacturing and operating the continuous evaporation type (Herb type) titanium getter pumps. In this paper cautions to be paid for troubles to be encountered in continuous running, effect of back-pumping by means of a diffusion pump on boosting a pumping speed, and ultimate pressure, are described.
Conclusions for Herb type pump are as follows ; in the present step, it is not suitable for ultra-high vacuum application, while its ultimate pressure is limited in the region between 10^-7 to 5 × 10^-8 mmHg. The occluded gas in the titanium wire released during continuous feeding and evaporation may be a gas source which limit the ultimate pressure. But it may be useful for obtaining 10^-6-10^-7 mmHg in short pumping time in cooperation with the diffusion pump. It is better to appreciate the titanium getter pump as one of good trap for active gases, but poor one for inert gases and organic vapors.
Flashing type absorber pump is very simple in construction, but is suitable for metal ultra-high vacuum system when it is used with a L - N trap and a diffusion pump.
Triode type pump such as Huber's, and Alpert's, or Hall's modyfication of Penning type pump are suitable for glass ultrahigh vacuum system, because they have appreciable pumping speed for helium. Desorption of the occluded gases, however, will be a problem.

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A resume of the methods for the production of pressures in the 10^-910^-10mmHg range in large metal systems is presented. The following pumping methods are discussed : mec anical pumps, getter pumps, ion-getter pumps, cryogenic pumps, and diffusion pump-trap systems. For large metal systems, the most practical pumping method found is the diffusion pump-trap system; cryogenic pumping can offer higher pumping speed per unit area where its higher cost is acceptable.
A 1300 liter volume space simulation chamber, now operating in the 10^-910^-10mmHg range, is described. Construction techniques, seals, and baking procedures are described. The problems arising in building even larger systems are analysed.

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