Historic Sundial

The sundial shown in the photo below was installed about 150 years ago.

The raised fin like part of the sundial is called a gnomon.  This gnomon, cast a shadow that basically marks the time of day as shown in the horizontal plate.

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Bastard tuck pointing

In the photo below you can see examples of what is known as bastard tuck pointing. Unlike the typical brick tuck pointing done at historic brick buildings to maintain the masonry mortar joints, bastard tuck pointing is normally done at a time or shortly after the time of original construction of a wall. Bastard tuck pointing is done not necessarily for preservation and maintenance of the wall for functional reasons such as protection from the elements and weather, instead it’s done more aesthetics. Bastard tuck pointing is the application of a raised bead of mortar on top of the original bead of mortar used to build and set the stones or masonry units of the wall itself.

Brick Hod

A brick hod is a simple tool used for tending brick and masonry materials and units. The picture below is from a pre-1930’s

In this blog post, we give a special thanks to Mark Stansbury, for permission to repost this image from his blog to ours. Stop by and check out Mark’s site at http://trowelcollector.blogspot.com

Today we commonly use a clamping brick carrier, a clamp with a handle to lift about a dozen bricks at a time, to pick up and tend brick to our masons instead. You may be able to get a sense from the image, but if not imagine the brick hod shown is attached to long pole, all told standing up to the full height of a man.

As one technology changes other technologies, in this case tools, are impacted. Brick hods are still commercially available today and even used in certain cases; however, with long boom rough terrain site navigable forklifts available today our simple industrial ergonomic efficiencies have changed as well. From about 150+ years ago up to about maybe 40 years ago, masonry units were delivered to site on train, cart or truck. Today, we can often get the masonry units loaded by machine much closer to the actual location of installation. However we still have to tend the masonry units to the Mason. Tending is the name for essentially handing the masonry unit to the Mason before the Mason carefully sets the masonry unit in place. Tending sounds very simple, almost unnecessary but it requires a lot of tough, backbreaking labor. Today we more commonly use the clamping brick carrier instead of a brick hod.

Modern Cement Mortar

Modern cement masonry mortar is the combination of modern cement mix, water, and a fine aggregate such as sand. There are also various types of pre-mixed cement have different ratings based on strength. Modern cement mortar may have many advantages over historic mortar: cost / volume ratio, market accessibility and availability, compressive strength, tensile strength, modulus of elasticity, permeability and resistance to moisture permeance, etc, etc.

While popularly used for modern construction, modern cement mortar should not be used to replace degraded joints in historic masonry. The modern cement is much harder than the traditional lime mortar and the inconsistency can cause serious damage to the structure.

Click here to go to the list of all items on Capitol Hill Historic Masonry.

Historic lime mortar joint with efflorescence

I like this picture for several reasons, in just this one photo you can see so many things.

This is a historic common brick, not a pressed brick.

It’s a wide mortar joint typical of plaster covered or exposed rear exteroor walls of the time, about late 1800’s.

There are subtle signs of efflorescence salts around the edge of the mortar joint.

You can see the large chunks of quicklime in the mortar joint.

A perfect example of terrible tuckpointing

The following pictures are from a chimney we repaired and Tuckpointed BEFORE we fixed it.

Some previous contractor went and tuckpointed the mortar joints with something that looks like the small batch cement sold in big box stores in small bags for floor leveling and the like.

It’s hard to tell what the previous contractor was thinking, the mortar is incompatible with the existing, too strong, not equivalently permeable, disimilisr modulus of elasticity, different tensile strength. You can see all of this from the photosexcept for the permeability which is an educated guess on my part because I know it to be a dark colored modern mortar.

One of the other main details about this mortar is the lack of sand grit is visually apparent. It is likely there is still a high silica content in this cement but likely at a much finer sieve, that is one of the reasons I suspect it might be a feather edge type of cement leveling product.

And of course, by the way, the previous contractor left messy mortar stains all over the face of the brick which look so bad you can actually see it from the street level.