In continuing the previous study, the authors reported in the present paper the results of further studies on Italian and Japanese puzzolanas and puzzolanic Portland cements. The brief summeries are abstracted from the original Japanese paper, as following:
(1) Three Italian puzzolanas, which were sent from Dr. C. Vittori, Società Anonima Italiana, Per la Produzione Calci e Cementi di Segni, Roma, Italiana, two Japanese puzzolanas, one siliceous earth (Keisan-Hakudo), one spent shale, and two blast furnace slags were compared on their specific gravities, chemical compositions, etc. The results are tabulated in the following tables.
Table 1. Results of Total Analysis
Table 2. Results of Specific Gravity and Soluble Analysis by 10%-NaOH and 5%-HCl Solutions
(2) These Italian and Japanese puzzolanic materials were mixed with Portland cement and ground intimately to various puzzolanic Portland cements. These samples were compared on their physical properties and chemical compositions, as shown in the following table 3.
(3) These samples of (1) puzzolanic Portland cements and (2) puzzolanic lime cements were compared on their hydraulic properties of mortar strength by the special testing method of compressive strength, which had been proposed by the present author (S. Nagai, Journ. Soc. Chem. Ind., Japan, 1929, 32, 635, 641; 1930, 33, 129; 1931, 34, 290; Tonindustrie=Zeitung, 1929, 53, 1048) and composed from small cylindrical testing piece (Dia. 2cm and Length 3cm), and used 1:3-cement sand mortar of high water-cement ratio (w/c=0.60-0.70) or so-called plastic mortar for moulding. The results were obtained in the following table 3.
Tabl. 3. Results of Compressive Strengths by Plastic Mortar Moulded to Small Cylindrical Test Pieces
(4) Again, these Italian and Japanese puzzolanic materials were mixed with slaked lime and ground intimately to puzzolanic lime cement. These cement samples were also compared on their physical properties and chemical compositions, as shown in the following table.
Table 4. Mixing Proportions, Physical Properties and Chemical Compositions of Italian and Japanese Puzzolanic Portland Cements and Puzzolanic Lime Cements
(5) These samples of (1) puzzolanic Portland cements and (2) puzzolanic lime cements were also compared on their soundness or expansion in the course of hardening by the methods of Lechatelier's calliper and Bauschinger's apparstus. From the results, it was observed that puzzolanic Portland cements are bettter or have smaller expansion than puzzolanic lime cements.
In conclusion, the suthors wish to express their hearty thanks to Prof. G. Malquori, Instituto Chimico, Roma Universita, Catania, Italiana and Dr. C. Vittori, Società Anonima Italiana, Per la Produzione Calci e Cementi di Segni, Roma, Italiana, for the kind sending of Italian puzzolanas and puzzolanic Portland cements.

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On continuing the previous studies, the authors reported, in the present paper, the results of further studies on various points of mixed Portland cements. The brief summaries are abstracted from the original Japanese paper, as following:
(1) The admixtures, which were used in the present studies, have the following chemical compositions.
Table 1. Total Analysis of Admixtures
Table 2. Soluble Analysis of Admixtures by Testing with Solutions of 10% NaOH and 5% HCl
(2) Various samples of mixed Portland cements were prepared by mixing common Portland cement clinker and these admixtures in proportions 60:40 and 80:20, and grinding with 2-3% of gypsum to fine powders by a laboratory pot mill, of which the fineness were nearly equal to the commercial Portland cement, i.e., the percentage of residue on 4900meshes/cm² sieve being 2-3%. The physical properties and chemical compositions are shown in the following tables.
Table 3. Mixing Proportions, Physical Properties of Mixed Portland Cements
Table 4. Chemical Compositions of Mixed Portland Cements
(3) The strengths of 1:3-cement-mortars of these cements were tested by (a) the ordinary method of specifications of Portland cement and blast fu nace slag cement in Japanese Engineering Standards JES 28 and JES 29 with dry mortar, and (b) the modifies method proposed by G. Haegermann in Germany (Protokoll der Tagung des Vereins deutscher Portland-Zement-Fabrikanten, E. V., Sept. 1929, 35; Reports of New International Association for Testing Materials, Zuerich, 1931, 669) and M. Ros in Switzerland (Diskussionsberichte Nr. 1, Nr. 10 & Nr. 60, Eidgenoessische Materialpruefungsanstalt, Eidg. Tech, Hochschuele, Zuerich) with wet mortar. Their results are tabulated in the following table 5 and 6.
Table 5. Compressive Strength (Cd) and Tensile Strength (T) of 1:3-Dry Mortar Tested by Standard Method of Specifications JES 28 and JES 29
Table 6. Compressive Strength (Cw) and Bending Strength (B) of 1:3-Wet Mortar Tested by Modified Method of Haegermann or Ros
(4) Ratios between these various results of strength testes were calculated and discussed the relations of these ratios and the properties of mixed Portland cements. These ratios are tabulated in the following table 7. These results are very well coincided with those reported by Haegermann or Ros (loc. cit).
Table 7. Ratios of Various Sorts of Strengths of 1:3-Dry and Wet Mortars
(5) The authors are now further studying on various points of mixed Portland cements and their results will be hereafter reported in the journal.

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In continuing the previous study, the author reports in present paper on the influence of 0.5% fluorspar in the high silica and lime raw mixture of H. M. above 2.15.
The auther burnt the raw mixtures of H. M., as clinker, 2.18, 2.20, 2.24 and 2.31 which are difficult on the usual burning, and got good cements with H. M. up to 2.24 by adding 0.5% fluorspar.

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The author has studied on the effect of storage on Portland cement, packed in paper and jute bags. These bags were stored in a ordinary store house for 5 months, from April 3 to September 3, 1933.
The tests of the stored cement were carried out the every zones in the bags.
The results are: (1) The loss on ignition of the cement of the outer zone (2-3cm thick) was more remarkable than those of the next and central parts. (2) The setting time of the cement of the outer zone was retarded more than those of the next and central parts.
(3) The strength of the cement of the outer zone showed extraordinary decrement, i.e. 40-50 per cent in compression and 20 per cent in tension respectively.

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In continuing the previous study, the author reports on the testing of the concrete. The tests of the stored cement were carried out about the 3 zones in the bags, i.e. outher zone, next and central parts. In conclusion, the compressive strength of the concrete of the outer zone showed extraordinary decrement. The decrement of the strength of the concrete was more than that of the mortar by the ordinary method.

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1. A notable error of heat balance of the cement rotary kiln hitherto depends upon mismeasurements and miscalculations of radiation and convection heat losses of the kiln and cooler shell, chiefly.
Then author measured them by means of “elongation method”, which is contrived by myself, with a view to make a correct heat balance.
2. The loss due to flue dust, which is ignored as yet, play an important part of heat losses.
3. Author atempt to manifest the calculation method of heat balance in order to popularize it in practical use, expecting to improve of the kiln conditions and combustion efficiency of fuel, which is proposed by myself.

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Experiments have been made of microstructure and refractive indices of the synthetic products described in Part 1 with the following results:
(1) The 3CaO.SiO₂ samples prepared at 1800°C are pure analytically as well as optically. However they contain minute proportions of β 2CaO.SiO₂ type crystals.
(2) The 2CaO.SiO₂ sample prepared at 1700°C consists solely of α type. It is likely that β→γ inversion of the silicate takes place more suddenly than α→β.
(3) The 3CaO.2SiO₂ samples prepared at temperatures varying from 1450° to 1475°C seem to be composed of 3CaO.2SiO₂ (or α CaO.SiO₂), γ 2CaO.SiO₂ and α 2CaO.SiO₂, although they are almost pure 3CaO.2SiO₂ analytically.
(4) The CaO.SiO₂ sample prepared at 1500°C is almost pure α CaO.SiO₂⋅α CaO.SiO₂ crystals are not optically biaxial and positive, but are optically uniaxial and negative, their refractive indices being ωD=1.650 and εD=1.610.
(5) The results of the observations of those samples which were prepared at temperatures lower than the maxima but higher than 900°C agree very well with the results of the synthetic experiments given in Part 1.
(6) All compound prepared at temperatures under 1500°C, especially at 1300° to 1400°C, are apt to dust.

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X-ray analysis has been made of calcium aluminates by Debye-Scherrer's method. The samples were same witht those used for the study of microstructure in Part II and neither lime nor alumina have been detected in free state by the X-ray analysis
The interplanar distances dhkl in Å of the samples are shown in Table 1, those underlined being characteristic for each compound. v. s (very strong), s (strong), m (medium), w (weak) and v. w (very weak) in parenthesis indicate the intensity of lines. No. of line 3CaO⋅Al₂O₃ 5CaO⋅3Al₂O₃ CaO⋅Al₂O₃ 3CaO⋅5Al₂O₃
1 4.805(m) 4.457(m) 2 3.877(m) 3 3.635(w) 4 3.505(v. s) 5 3.495(w) 3.492(w) 3.459(w) 6 3.302(v. w) 3.266(w) 7 3.138(m) 3.175(w) 3.165(v. w) 8 3.087(m) 9 2.951(m) 2.965(s) 2.951(v. s) 2.972(s) 10 2.880(m) 11 2.763(w) 12 2.712(w) 13 2.682(v. s) 2.670(v. s) 2.650(w) 14 2.605(v. s) 15 2.542(m) 2.512(s) 2.582(m) 16 2.493(w) 17 2.432(s) 2.418(w) 18 2.387(v. w) 2.387(s) 2.383(m) 19 2.306(w) 2.307(v. w) 20 2.196(w) 2.195(m) 21 2.176(v. s) 2.176(m) 22 2.097(v. w) 2.145(w) 23 2.038(v. w) 2.065(w) 2.059(s) 24 2.010(w) 25 1.966(w) 26 1.936(v.s) 1.931(m) 1.935(v. w) 27 1.903(s) 1.903(w) 1.900(w) 28 1.857(v. w) 29 1.843(s) 1.847(v. w) 30 1.820(m) 1.811(v. w) 1.822(s)
The results do not agree satisfactorily with those of E. A. Harrington but coincide comparatively well with those given by S. Solacolu.

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