BY CAPTAIN SHOETT, R.N. 19 



lie required, to have the mark cut deeply in the rock, in the 

 exact spot which his tidal observations indicated as the mean 

 level of the ocean. 



I may here observe, that it is not essential that the mark be 

 made exactly at the mean level of the ocean, indeed it is more 

 desirable that it should be rather above the reach of the highest 

 tide, and the exact distance above the mean level recorded. 



The most desirable position for such another mark would be 

 near the North-West extremity of the island, in the vicinity 

 of Cape Grim. 



Mr. Lempriere, it is evident, carefully carried out these 

 directions, for on a tablet still existing a little above the tide 

 mark in question is the following record. " On the rock 

 fronting this stone a line denoting the height of the tide now 

 struck on the 1st July, 1841, mean time 4h. 44 m. p.m.; 

 moon's age 12 days ; height of water in tide gauge 6 ft. 1 in." 



It is stated by my informant, Mr. T. Mason, that the words 

 and figures underlined are nearly obliterated, and that he has 

 given what they appear to be. It is unfortunate, also, that no 

 other records can be found relating to Mr. Lempriere's tidal 

 observations, although I have searched all local records. I have 

 also applied to Capt. W. J. Z. Wharton, E.N., Hydrographer 

 of the Admiralty, with the view of ascertaining if they had 

 any records relating to Mr. Lempriere's observations at Port 

 Arthur, but in answer I learn that no records of tidal 

 observations have ever been received at the Admiralty. 



Capt. Wharton at the same time informs me that the 

 approximate time of high water on 1st July, 1841, was 

 5 h. 35 m., p.m., that is nearly an hour later than the apparent 

 record on the tablet. If we now assume that the tide 

 now struck refers to high water, which is most probable, we 

 have some means of determining whether any change has since 

 occurred in the relative levels of sea and land. 



Mr. Mason, at my request, very kindly ascertained the time 

 of low water on February 24th, 1888, at 11 h. 45 m. a.m., which 

 day corresponds relatively with the muon's age 47 years 

 previously. 



At this low water level the mark was found to be 2ift. above. 

 This very closely corresponds with the normal difference between 

 these levels of low and high water, and would therefore indicate 

 that there has been practically no alteration of the relative 

 levels of sea and land during the last 47 years. This, however, 

 only bears witness to possible movements in the Southern 

 portion of the island. As regards the N"orthern portion there 

 is no definite knowledge ; but it is interesting to place on 

 record, that Captain Miles has learnt from the half-casts in the 

 Purneaux G-roup they have noticed within the last few years 



